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v3.5.0.2

Debt (Details) | 1 Months Ended | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Aug. 31, 2016 USD ($) | Feb. 29, 2016 USD ($) | Sep. 30, 2016 USD ($) $ / shares shares | Sep. 30, 2015 USD ($) | Sep. 30, 2016 USD ($) trading_day $ / shares shares | Sep. 30, 2015 USD ($) | Dec. 31, 2015 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |
Loss on debt extinguishment |  |  | $ 75,223,000 | $ 0 | $ 90,531,000 | $ 0 |
Federal Home Loan Bank advances |  | $ 155,000,000 |  |  |  |  |
Federal Home Loan Bank, advances, interest rate (as a percent) |  | 1.91% | 1.91% |  | 1.91% |  |
Federal Home Loan Bank advances, collateral, value of principal, percent (as a percent) |  | 102.00% |  |  |  |  |
Deferred issuance costs |  |  | $ 11,500,000 |  | $ 11,500,000 |  | $ 11,200,000
Convertible senior notes (note 3) |  |  | 349,073,000 |  | 349,073,000 |  | 822,301,000
Convertible junior subordinated debentures (note 3) |  |  | 256,872,000 |  | 256,872,000 |  | 389,522,000
Long-term debt, par value |  |  | 1,189,500,000 |  | 1,189,500,000 |  | 1,223,000,000
Long-term debt, carrying value |  |  | 1,178,000,000 |  | 1,178,000,000 |  | 1,211,800,000
Holding company cash and investments |  |  | $ 329,000,000 |  | $ 329,000,000 |  |
Modified duration of holding company investments (in years) |  |  |  |  | 1 year 7 months 6 days |  |
Interest payments made |  |  |  |  | $ 31,500,000 | $ 32,800,000 |
Scenario, Previously Reported |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Long-term debt, carrying value |  |  |  |  |  |  | 1,223,000,000
Restatement Adjustment |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Long-term debt, carrying value |  |  |  |  |  |  | (11,200,000)
Adjustments for New Accounting Pronouncement | Long-term Debt |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Deferred issuance costs |  |  |  |  |  |  | 11,200,000
Adjustments for New Accounting Pronouncement | Other Assets |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Deferred issuance costs |  |  |  |  |  |  | $ (11,200,000)
Senior Notes | 5.75% Senior Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Stated interest rate (in hundredths) | 5.75% |  | 5.75% |  | 5.75% |  | 5.75%
Aggregate principal amount | $ 425,000,000 |  |  |  |  |  |
Net proceeds from issuance of debt | $ 418,100,000 |  |  |  |  |  |
Redemption price, percentage (in hundredths) | 100.00% |  |  |  |  |  |
Expenses associated with issuance of notes | $ 1,200,000 |  |  |  |  |  |
Ownership threshold for declaration of due and payable (at least) (as a percent) | 25.00% |  |  |  |  |  |
Long-term debt, par value |  |  | $ 425,000,000 |  | $ 425,000,000 |  | $ 0
Senior Notes | 5.75% Senior Notes | U.S. Treasury Rate |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Basis spread on redemption premium (as a percent) | 0.50% |  |  |  |  |  |
Convertible Senior Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Stated interest rate (in hundredths) |  |  | 5.00% | 5.00% | 5.00% | 5.00% | 5.00%
Extinguishment of debt amount |  |  |  |  | $ 188,500,000 |  |
Purchase price of debt purchased |  |  |  |  | $ 195,500,000 |  |
Reduction in shares for computation of earnings per share (in shares) | shares |  |  |  |  | 14,000,000 |  |
Convertible senior notes (note 3) |  |  |  |  |  |  | $ 331,500,000
Long-term debt, par value |  |  | $ 145,000,000 |  | $ 145,000,000 |  | 333,500,000
Conversion rate (in shares per $1,000 note) | shares |  |  |  |  | 74.4186 |  |
Principal amount of notes used in determining conversion rate |  |  | $ 1,000 |  | $ 1,000 |  |
Initial conversion price (in dollars per share) | $ / shares |  |  | $ 13.44 |  | $ 13.44 |  |
Interest payments made |  |  |  |  | $ 6,900,000 | $ 8,600,000 |
Convertible Senior Notes | Scenario, Previously Reported |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Convertible senior notes (note 3) |  |  |  |  |  |  | 333,500,000
Convertible Senior Notes | Restatement Adjustment |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Convertible senior notes (note 3) |  |  |  |  |  |  | (2,000,000)
Convertible Senior Notes | 2% Convertible Senior Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Stated interest rate (in hundredths) |  |  | 2.00% |  | 2.00% |  |
Extinguishment of debt amount |  |  | $ 292,400,000 |  |  |  |
Repayments of debt, aggregate repurchase price |  |  | 362,100,000 |  |  |  |
Purchase price of debt purchased |  |  | $ 230,700,000 |  |  |  |
Shares issued for repayment of debt | shares |  |  | 18,300,000 |  |  |  |
Reduction in shares for computation of earnings per share (in shares) | shares |  |  | 42,100,000 |  |  |  |
9% Debentures |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Stated interest rate (in hundredths) |  |  | 9.00% | 9.00% | 9.00% | 9.00% |
Extinguishment of debt amount |  | $ 132,700,000 |  |  |  |  |
Purchase price of debt purchased |  | $ 150,700,000 |  |  |  |  |
Reduction in shares for computation of earnings per share (in shares) | shares |  |  |  |  | 9,800,000 |  |
Loss on debt extinguishment |  |  |  |  | $ 8,300,000 |  |
Reacquisition of convertible junior subordinated debentures-equity component |  |  |  |  | $ (6,300,000) |  |
Convertible junior subordinated debentures (note 3) |  |  |  |  |  |  | 389,500,000
9% Debentures | Scenario, Previously Reported |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Convertible junior subordinated debentures (note 3) |  |  |  |  |  |  | 389,500,000
9% Debentures | Restatement Adjustment |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Convertible junior subordinated debentures (note 3) |  |  |  |  |  |  | $ 0
Convertible Junior Subordinated Debentures, interest at 9% per annum, due April 2063 |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Stated interest rate (in hundredths) |  | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00%
Long-term debt, par value |  |  | $ 256,900,000 |  | $ 256,900,000 |  | $ 389,500,000
Conversion rate (in shares per $1,000 note) | shares |  |  |  |  | 74.0741 |  |
Principal amount of notes used in determining conversion rate |  |  | $ 1,000 |  | $ 1,000 |  |
Initial conversion price (in dollars per share) | $ / shares |  |  | $ 13.50 |  | $ 13.50 |  |
Period preceding election to convert |  |  |  |  | 5 days |  |
Interest payments made |  |  |  |  | $ 15,900,000 | $ 17,500,000 |
2% Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Stated interest rate (in hundredths) |  |  | 2.00% | 2.00% | 2.00% | 2.00% | 2.00%
Redemption price, percentage (in hundredths) |  |  |  |  | 100.00% |  |
Convertible senior notes (note 3) |  |  |  |  |  |  | $ 490,800,000
Long-term debt, par value |  |  | $ 207,600,000 |  | $ 207,600,000 |  | 500,000,000
Conversion rate (in shares per $1,000 note) | shares |  |  |  |  | 143.8332 |  |
Principal amount of notes used in determining conversion rate |  |  | $ 1,000 |  | $ 1,000 |  |
Initial conversion price (in dollars per share) | $ / shares |  |  | $ 6.95 |  | $ 6.95 |  |
Threshold number of trading days (in days) | trading_day |  |  |  |  | 20 |  |
Threshold consecutive trading days (in days) |  |  |  |  | 30 days |  |
Percentage of conversion price (in hundredths) |  |  | 130.00% |  | 130.00% |  |
Convertible debt, conversion price (in dollars per share) | $ / shares |  |  | $ 9.03 |  | $ 9.03 |  |
Interest payments made |  |  |  |  | $ 7,000,000 | $ 5,000,000 |
2% Notes | Scenario, Previously Reported |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Convertible senior notes (note 3) |  |  |  |  |  |  | 500,000,000
2% Notes | Restatement Adjustment |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Convertible senior notes (note 3) |  |  |  |  |  |  | (9,200,000)
FHLB Advance |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Long-term debt, par value |  |  | $ 155,000,000 |  | 155,000,000 |  | $ 0
Interest payments made |  |  |  |  | $ 1,700,000 | $ 0 |
Senior Notes, interest at 5.375% per annum, due November 2015 |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Stated interest rate (in hundredths) |  |  | 5.375% | 5.375% | 5.375% | 5.375% |
Interest payments made |  |  |  |  | $ 0 | $ 1,700,000 |

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