XML 112 R92.htm IDEA: XBRL DOCUMENT
v3.3.1.900

Investment Securities (Rollforward of Fair Value Measurements by Level) (Details) | 12 Months Ended
--- | ---
Dec. 31, 2015 USD ($) Investment | Dec. 31, 2014 USD ($) Investment | Dec. 31, 2013 USD ($)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | $ 3,343,600,000 | $ 3,889,000,000 |
Total realized and unrealized gains (losses) | (226,800,000) | 83,300,000 |
Amortization/Accretion | (19,600,000) | (18,500,000) |
Purchases | (2,377,100,000) | 2,868,500,000 |
Sales | (2,210,100,000) | 3,500,200,000 |
Net change in investments related to purchases and sales of consolidated/unconsolidated affiliates | (394,500,000) | 21,500,000 |
Fair Value, Assets Measured on Recurring Basis, Other | (61,400,000) |  |
Fair Value, Assets Measured on Recurring Basis, Measurement Input Reconciliation, Assets, Exchange |  | 0 |
Transfers in | 41,800,000 | 53,000,000 |
Transfers out | (41,800,000) | (53,000,000) |
Fair value investments | 4,050,900,000 | 3,343,600,000 | $ 3,889,000,000
Net realized and unrealized investment gains | 225,400,000 | 78,500,000 | 133,900,000
Discontinued Operations |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fixed maturity investments reclassified to assets held for sale (1) |  |  | (236,300,000)
Net realized and unrealized investment gains | 15,100,000 | 205,400,000 | 27,800,000
Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 3,720,400,000 |  |
Fair value investments | 4,262,200,000 | 3,720,400,000 |
US Government and agency obligations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 105,200,000 |  |
Fair value investments | 160,000,000 | 105,200,000 |
Fixed maturity investments | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 2,422,000,000 |  |
Fair value investments | 2,639,700,000 | 2,422,000,000 |
Other long-term investments | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 309,900,000 |  |
Fair value investments | 297,300,000 | 309,900,000 |
Short-term investments | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 376,800,000 | 310,400,000 |
Fair value investments | 211,300,000 | 376,800,000 | 310,400,000
Debt securities issued by corporations |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 1,171,700,000 |  |
Fair value investments | 1,000,000,000 | 1,171,700,000 |
Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 1,171,700,000 |  |
Fair value investments | 1,000,000,000 | 1,171,700,000 |
Mortgage-backed and asset-backed securities |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 967,900,000 |  |
Fair value investments | 1,167,000,000 | 967,900,000 |
Mortgage-backed and asset-backed securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 967,900,000 |  |
Fair value investments | 1,167,000,000 | 967,900,000 |
Municipal obligations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 82,200,000 |  |
Fair value investments | 228,800,000 | 82,200,000 |
Foreign government, agency and provincial obligations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 10,800,000 |  |
Fair value investments | 1,200,000 | 10,800,000 |
Preferred stocks | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 84,200,000 |  |
Fair value investments | 82,700,000 | 84,200,000 |
Level 1 Inputs |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 550,600,000 | 997,200,000 |
Total realized and unrealized gains (losses) | (263,000,000) | 50,100,000 |
Amortization/Accretion | 0 | 100,000 |
Purchases | (814,500,000) | 886,900,000 |
Sales | (825,700,000) | 1,384,200,000 |
Net change in investments related to purchases and sales of consolidated/unconsolidated affiliates | (394,500,000) | (2,700,000) |
Fair Value, Assets Measured on Recurring Basis, Other | (43,500,000) |  |
Fair Value, Assets Measured on Recurring Basis, Measurement Input Reconciliation, Assets, Exchange |  | 3,400,000 |
Transfers in | 0 | 0 |
Transfers out | (1,200,000) | (200,000) |
Fair value investments | 1,152,200,000 | 550,600,000 | 997,200,000
Level 1 Inputs | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 926,900,000 |  |
Fair value investments | 1,363,500,000 | 926,900,000 |
Level 1 Inputs | US Government and agency obligations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 51,200,000 |  |
Fair value investments | 133,400,000 | 51,200,000 |
Level 1 Inputs | Fixed maturity investments | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 51,800,000 |  |
Fair value investments | 134,000,000 | 51,800,000 |
Level 1 Inputs | Other long-term investments | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Level 1 Inputs | Short-term investments | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 376,300,000 |  |
Fair value investments | 211,300,000 | 376,300,000 |
Level 1 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Level 1 Inputs | Mortgage-backed and asset-backed securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Level 1 Inputs | Municipal obligations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Level 1 Inputs | Foreign government, agency and provincial obligations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 600,000 |  |
Fair value investments | 600,000 | 600,000 |
Level 1 Inputs | Preferred stocks | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Level 2 Inputs |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 2,372,900,000 | 2,575,400,000 |
Total realized and unrealized gains (losses) | 13,700,000 | 8,900,000 |
Amortization/Accretion | (19,600,000) | (18,700,000) |
Purchases | (1,436,000,000) | 1,805,300,000 |
Sales | (1,286,000,000) | 2,065,900,000 |
Net change in investments related to purchases and sales of consolidated/unconsolidated affiliates | 0 | 24,200,000 |
Fair Value, Assets Measured on Recurring Basis, Other | 0 |  |
Fair Value, Assets Measured on Recurring Basis, Measurement Input Reconciliation, Assets, Exchange |  | (9,300,000) |
Transfers in | 41,800,000 | 53,000,000 |
Transfers out | 0 | 0 |
Fair value investments | 2,531,400,000 | 2,372,900,000 | 2,575,400,000
Level 2 Inputs | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 2,373,400,000 |  |
Fair value investments | 2,531,400,000 | 2,373,400,000 |
Level 2 Inputs | US Government and agency obligations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 54,000,000 |  |
Fair value investments | 26,600,000 | 54,000,000 |
Level 2 Inputs | Fixed maturity investments | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 2,293,800,000 |  |
Fair value investments | 2,435,700,000 | 2,293,800,000 |
Level 2 Inputs | Other long-term investments | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 5,700,000 |  |
Fair value investments | 0 | 5,700,000 |
Level 2 Inputs | Short-term investments | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 500,000 |  |
Fair value investments | 0 | 500,000 |
Level 2 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 1,166,400,000 |  |
Fair value investments | 1,000,000,000 | 1,166,400,000 |
Level 2 Inputs | Mortgage-backed and asset-backed securities |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 967,900,000 |  |
Fair value investments | 1,167,000,000 | 967,900,000 |
Level 2 Inputs | Mortgage-backed and asset-backed securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 967,900,000 |  |
Fair value investments | 1,167,000,000 | 967,900,000 |
Level 2 Inputs | Municipal obligations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 82,200,000 |  |
Fair value investments | 228,800,000 | 82,200,000 |
Level 2 Inputs | Foreign government, agency and provincial obligations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 10,200,000 |  |
Fair value investments | 600,000 | 10,200,000 |
Level 2 Inputs | Preferred stocks | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 13,100,000 |  |
Fair value investments | 12,700,000 | 13,100,000 |
Level 3 Inputs | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 420,100,000 |  |
Fair value investments | 367,300,000 | 420,100,000 |
Level 3 Inputs | US Government and agency obligations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Level 3 Inputs | Fixed maturity investments |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 76,400,000 | 81,800,000 |
Total realized and unrealized gains (losses) | 1,100,000 | 1,800,000 |
Amortization/Accretion | 0 | 100,000 |
Purchases | (35,300,000) | 39,600,000 |
Sales | 0 | 0 |
Net change in investments related to purchases and sales of consolidated/unconsolidated affiliates | 0 | 0 |
Fair Value, Assets Measured on Recurring Basis, Other | 0 |  |
Fair Value, Assets Measured on Recurring Basis, Measurement Input Reconciliation, Assets, Exchange |  | 5,900,000 |
Transfers in | 0 | 0 |
Transfers out | (40,600,000) | (52,800,000) |
Fair value investments | $ 70,000,000 | $ 76,400,000 | 81,800,000
Number of investments | Investment | 6 | 6 |
Level 3 Inputs | Fixed maturity investments | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | $ 76,400,000 |  |
Fair value investments | 70,000,000 | $ 76,400,000 |
Level 3 Inputs | Common equity securities |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 39,500,000 | 45,400,000 |
Total realized and unrealized gains (losses) | (7,800,000) | 6,200,000 |
Amortization/Accretion | 0 | 0 |
Purchases | 0 | 5,000,000 |
Sales | (43,700,000) | 17,100,000 |
Net change in investments related to purchases and sales of consolidated/unconsolidated affiliates | 0 | 0 |
Fair Value, Assets Measured on Recurring Basis, Other | (3,600,000) |  |
Fair Value, Assets Measured on Recurring Basis, Measurement Input Reconciliation, Assets, Exchange |  | 0 |
Transfers in | 0 | 0 |
Transfers out | 0 | 0 |
Fair value investments | 0 | 39,500,000 | 45,400,000
Level 3 Inputs | Other long-term investments |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 304,200,000 | 189,200,000 |
Total realized and unrealized gains (losses) | 29,200,000 | 16,300,000 |
Amortization/Accretion | 0 | 0 |
Purchases | (91,300,000) | 131,700,000 |
Sales | (54,700,000) | 33,000,000 |
Net change in investments related to purchases and sales of consolidated/unconsolidated affiliates | 0 | 0 |
Fair Value, Assets Measured on Recurring Basis, Other | (14,300,000) |  |
Fair Value, Assets Measured on Recurring Basis, Measurement Input Reconciliation, Assets, Exchange |  | 0 |
Transfers in | 0 | 0 |
Transfers out | 0 | 0 |
Fair value investments | 297,300,000 | 304,200,000 | 189,200,000
Level 3 Inputs | Other long-term investments | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 304,200,000 |  |
Fair value investments | 297,300,000 | 304,200,000 |
Carrying value of investment accounted for using the equity method | 3,800,000 | 5,200,000 | $ 6,800,000
Level 3 Inputs | Short-term investments | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Level 3 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 5,300,000 |  |
Fair value investments | 0 | 5,300,000 |
Level 3 Inputs | Mortgage-backed and asset-backed securities |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Level 3 Inputs | Mortgage-backed and asset-backed securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Level 3 Inputs | Municipal obligations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Level 3 Inputs | Foreign government, agency and provincial obligations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Level 3 Inputs | Preferred stocks | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 71,100,000 |  |
Fair value investments | 70,000,000 | 71,100,000 |
Prospector |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Net realized and unrealized investment gains | 800,000 | 4,000,000 |
Consumer | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 116,000,000 |  |
Fair value investments | 70,000,000 | 116,000,000 |
Consumer | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 259,200,000 |  |
Fair value investments | 253,300,000 | 259,200,000 |
Consumer | Level 1 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 115,900,000 |  |
Fair value investments | 70,000,000 | 115,900,000 |
Consumer | Level 1 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Consumer | Level 2 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 100,000 |  |
Fair value investments | 0 | 100,000 |
Consumer | Level 2 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 259,200,000 |  |
Fair value investments | 253,300,000 | 259,200,000 |
Consumer | Level 3 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Consumer | Level 3 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Financials | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 180,700,000 |  |
Fair value investments | 694,700,000 | 180,700,000 |
Financials | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 254,700,000 |  |
Fair value investments | 175,900,000 | 254,700,000 |
Financials | Level 1 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 141,200,000 |  |
Fair value investments | 694,700,000 | 141,200,000 |
Financials | Level 1 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Financials | Level 2 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Financials | Level 2 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 254,700,000 |  |
Fair value investments | 175,900,000 | 254,700,000 |
Financials | Level 3 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 39,500,000 |  |
Fair value investments | 0 | 39,500,000 |
Financials | Level 3 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Health Care [Member] | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 74,400,000 |  |
Fair value investments | 35,700,000 | 74,400,000 |
Health Care [Member] | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 181,800,000 |  |
Fair value investments | 151,300,000 | 181,800,000 |
Health Care [Member] | Level 1 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 74,400,000 |  |
Fair value investments | 35,700,000 | 74,400,000 |
Health Care [Member] | Level 1 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Health Care [Member] | Level 2 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Health Care [Member] | Level 2 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 181,800,000 |  |
Fair value investments | 151,300,000 | 181,800,000 |
Health Care [Member] | Level 3 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Health Care [Member] | Level 3 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Industrial | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 57,100,000 |  |
Fair value investments | 26,600,000 | 57,100,000 |
Industrial | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 107,300,000 |  |
Fair value investments | 135,600,000 | 107,300,000 |
Industrial | Level 1 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 57,100,000 |  |
Fair value investments | 26,600,000 | 57,100,000 |
Industrial | Level 1 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Industrial | Level 2 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Industrial | Level 2 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 102,000,000 |  |
Fair value investments | 135,600,000 | 102,000,000 |
Industrial | Level 3 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Industrial | Level 3 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 5,300,000 |  |
Fair value investments | 0 | 5,300,000 |
Utilities | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 18,100,000 |  |
Fair value investments |  | 18,100,000 |
Utilities | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 65,600,000 |  |
Fair value investments | 82,000,000 | 65,600,000 |
Utilities | Level 1 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 18,100,000 |  |
Fair value investments |  | 18,100,000 |
Utilities | Level 1 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Utilities | Level 2 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments |  | 0 |
Utilities | Level 2 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 65,600,000 |  |
Fair value investments | 82,000,000 | 65,600,000 |
Utilities | Level 3 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments |  | 0 |
Utilities | Level 3 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Energy | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 4,900,000 |  |
Fair value investments |  | 4,900,000 |
Energy | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 84,100,000 |  |
Fair value investments | 61,500,000 | 84,100,000 |
Energy | Level 1 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 4,900,000 |  |
Fair value investments |  | 4,900,000 |
Energy | Level 1 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Energy | Level 2 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments |  | 0 |
Energy | Level 2 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 84,100,000 |  |
Fair value investments | 61,500,000 | 84,100,000 |
Energy | Level 3 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments |  | 0 |
Energy | Level 3 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Technology | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 44,800,000 |  |
Fair value investments | 27,000,000 | 44,800,000 |
Technology | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 88,300,000 |  |
Fair value investments | 60,000,000 | 88,300,000 |
Technology | Level 1 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 44,800,000 |  |
Fair value investments | 27,000,000 | 44,800,000 |
Technology | Level 1 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Technology | Level 2 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Technology | Level 2 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 88,300,000 |  |
Fair value investments | 60,000,000 | 88,300,000 |
Technology | Level 3 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Technology | Level 3 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Communications | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 28,500,000 |  |
Fair value investments | 43,700,000 | 28,500,000 |
Communications | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 71,500,000 |  |
Fair value investments | 49,200,000 | 71,500,000 |
Communications | Level 1 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 28,500,000 |  |
Fair value investments | 43,700,000 | 28,500,000 |
Communications | Level 1 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Communications | Level 2 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Communications | Level 2 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 71,500,000 |  |
Fair value investments | 49,200,000 | 71,500,000 |
Communications | Level 3 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Communications | Level 3 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Materials | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 12,000,000 |  |
Fair value investments |  | 12,000,000 |
Materials | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 51,700,000 |  |
Fair value investments | 31,200,000 | 51,700,000 |
Materials | Level 1 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 12,000,000 |  |
Fair value investments |  | 12,000,000 |
Materials | Level 1 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Materials | Level 2 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments |  | 0 |
Materials | Level 2 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 51,700,000 |  |
Fair value investments | 31,200,000 | 51,700,000 |
Materials | Level 3 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments |  | 0 |
Materials | Level 3 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Other | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 75,200,000 |  |
Fair value investments | 74,400,000 | 75,200,000 |
Other | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 7,500,000 |  |
Fair value investments | 0 | 7,500,000 |
Other | Level 1 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 1,900,000 |  |
Fair value investments | 0 | 1,900,000 |
Other | Level 1 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Other | Level 2 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 73,300,000 |  |
Fair value investments | 74,400,000 | 73,300,000 |
Other | Level 2 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 7,500,000 |  |
Fair value investments | 0 | 7,500,000 |
Other | Level 3 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Other | Level 3 Inputs | Debt securities issued by corporations | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Fair value investments | 0 | 0 |
Exchange Traded Funds [Member] | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 141,800,000 |  |
Exchange Traded Funds [Member] | Level 1 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 120,500,000 |  |
Exchange Traded Funds [Member] | Level 2 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 21,300,000 |  |
Exchange Traded Funds [Member] | Level 3 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 0 |  |
Common equity securities | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 611,700,000 |  |
Fair value investments | 1,113,900,000 | 611,700,000 |
Common equity securities | Level 1 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 498,800,000 |  |
Fair value investments | 1,018,200,000 | 498,800,000 |
Common equity securities | Level 2 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 73,400,000 |  |
Fair value investments | 95,700,000 | 73,400,000 |
Common equity securities | Level 3 Inputs | Common equity securities | Fair value measured on a recurring basis |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 39,500,000 |  |
Fair value investments | 0 | 39,500,000 |
Symetra |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Total realized and unrealized gains (losses) | (258,800,000.0) |  |
Affordable Housing Development Fund [Member] | Other long-term investments |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value investments | 16,800,000 |  |
Fair value investments | $ 14,700,000 | $ 16,800,000 |

X
- Definition The sum of the periodic adjustments of the differences between securities' face values and purchase prices that are charged against earnings. This is called accretion if the security was purchased at a discount and amortization if it was purchased at premium. As a noncash item, this element is an adjustment to net income when calculating cash provided by or used in operations using the indirect method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585 + Details
Name: | us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Fair value portion of investments accounted under the equity method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 25 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=35740979&loc=d3e32014-111567 + Details
Name: | us-gaap_EquityMethodInvestmentsFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
Name: | us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting and losses recognized for other than temporary impairments (OTTI) of the subject investments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (c)-(e) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.7(c),9(a)) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27405-111563 + Details
Name: | us-gaap_GainLossOnInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=51813488&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 + Details
Name: | us-gaap_InvestmentsFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The cash outflow associated with the purchase of all investments (debt, security, other) during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3213-108585 + Details
Name: | us-gaap_PaymentsToAcquireInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The cash inflow associated with the sale, maturities, repayments and calls of securities classified as trading securities and held for investment purposes. Excludes proceeds from trading securities purchased and held principally for the purpose of selling them in the near term (thus held for only a short period of time). + References No definition available. + Details
Name: | us-gaap_ProceedsFromSaleAndMaturityOfTradingSecuritiesHeldforinvestment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition This element represents the amount of the total realized and unrealized (holding) gains or losses for the period which are included in the statement of income. + References No definition available. + Details
Name: | wtm_FairValueAssetsMeasuredOnRecurringBasisGainLossIncludedInEarnings
Namespace Prefix: | wtm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition This element represents transfers in to one of the levels in the fair value hierarchy for assets measured at fair value on a recurring basis. + References No definition available. + Details
Name: | wtm_FairValueAssetsMeasuredOnRecurringBasisTransfersIn
Namespace Prefix: | wtm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition This element represents transfers out of one of the levels in the fair value hierarchy for assets measured at fair value on a recurring basis. + References No definition available. + Details
Name: | wtm_FairValueAssetsMeasuredOnRecurringBasisTransfersOut
Namespace Prefix: | wtm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition This element represents exchanges in/ out of levels in the fair value hierarchy for assets measured at fair value on a recurring basis. + References No definition available. + Details
Name: | wtm_FairValueAssetsMeasuredonRecurringBasisMeasurementInputReconciliationAssetsExchange
Namespace Prefix: | wtm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition This element represents other reconciling items in the fair value hierarchy for assets measured at fair value on a recurring basis. + References No definition available. + Details
Name: | wtm_FairValueAssetsMeasuredonRecurringBasisOther
Namespace Prefix: | wtm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Net change in investments related to purchases and sales of consolidated/unconsolidated affiliates + References No definition available. + Details
Name: | wtm_NetChangeInInvestmentsRelatedToPurchasesAndSalesOfConsolidatedunconsolidatedAffiliates
Namespace Prefix: | wtm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Number of Investments + References No definition available. + Details
Name: | wtm_NumberOfInvestments
Namespace Prefix: | wtm_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Represents the fair value of trading debt securities re-classified to assets held for sale. + References No definition available. + Details
Name: | wtm_TradingSecuritiesDebtReclassifiedToAssetsHeldForSale
Namespace Prefix: | wtm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_StatementOperatingActivitiesSegmentAxis=us-gaap_SegmentDiscontinuedOperationsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsRecurringMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_USTreasuryAndGovernmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_FixedMaturitiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_OtherLongTermInvestmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_ShortTermInvestmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_CorporateDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_AssetBackedSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_MunicipalBondsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_ForeignGovernmentDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_PreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel1Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel2Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_EquitySecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=wtm_ProspectorFundsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | invest_InvestmentSectorAxis=wtm_ConsumerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | invest_InvestmentSectorAxis=wtm_FinancialsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | invest_InvestmentSectorAxis=wtm_HealthCareMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | invest_InvestmentSectorAxis=wtm_IndustrialMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | invest_InvestmentSectorAxis=wtm_EnergyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | invest_InvestmentSectorAxis=wtm_UtilitiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | invest_InvestmentSectorAxis=wtm_TechnologyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | invest_InvestmentSectorAxis=wtm_CommunicationsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | invest_InvestmentSectorAxis=wtm_BasicMaterialsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | invest_InvestmentSectorAxis=wtm_OtherSectorMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | invest_InvestmentSectorAxis=us-gaap_ExchangeTradedFundsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | invest_InvestmentSectorAxis=us-gaap_EquitySecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | invest_InvestmentAxis=wtm_SymetraMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | invest_InvestmentAxis=wtm_AffordableHousingDevelopmentFundMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |