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Variable Annuity Reinsurance (Details) | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended |  | 3 Months Ended | 9 Months Ended |  |  |  |  |  |  |  | 3 Months Ended | 9 Months Ended |  |  | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended
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Sep. 30, 2011 USD ($) rating state | Sep. 30, 2010 USD ($) | Sep. 30, 2011 USD ($) rating state | Sep. 30, 2010 USD ($) | Sep. 30, 2011 WM Life Re USD ($) | Sep. 30, 2010 WM Life Re USD ($) | Sep. 30, 2011 WM Life Re USD ($) | Sep. 30, 2010 WM Life Re USD ($) | Dec. 31, 2010 WM Life Re USD ($) | Sep. 30, 2011 WM Life Re Variable annuity reinsurance. USD ($) | Sep. 30, 2010 WM Life Re Variable annuity reinsurance. USD ($) | Sep. 30, 2011 WM Life Re Variable annuity reinsurance. USD ($) | Sep. 30, 2010 WM Life Re Variable annuity reinsurance. USD ($) | Sep. 30, 2011 WM Life Re Cash. USD ($) | Dec. 31, 2010 WM Life Re Cash. USD ($) | Sep. 30, 2011 WM Life Re Fixed maturity investments USD ($) | Dec. 31, 2010 WM Life Re Fixed maturity investments USD ($) | Sep. 30, 2011 WM Life Re Short-term investments USD ($) | Dec. 31, 2010 WM Life Re Short-term investments USD ($) | Sep. 30, 2011 WM Life Re Citigroup USD ($) | Sep. 30, 2011 WM Life Re Royal Bank of Scotland USD ($) | Sep. 30, 2011 WM Life Re Bank of America USD ($) | Sep. 30, 2011 WM Life Re Barclays USD ($) | Sep. 30, 2011 WM Life Re Nomura USD ($) | Sep. 30, 2011 WM Life Re JP Morgan USD ($) | Sep. 30, 2011 WM Life Re BNP Paribas USD ($) | Sep. 30, 2011 WM Life Re Goldman Sachs USD ($) | Sep. 30, 2011 Level 3 Inputs Variable annuity reinsurance. USD ($) | Sep. 30, 2011 Level 3 Inputs Variable annuity reinsurance. USD ($) | Sep. 30, 2011 Variable annuity reinsurance. USD ($) | Sep. 30, 2011 Variable annuity reinsurance. JPY (¥) | Dec. 31, 2010 Variable annuity reinsurance. USD ($) | Dec. 31, 2010 Variable annuity reinsurance. JPY (¥) | Sep. 30, 2011 Level 1 Inputs USD ($) | Sep. 30, 2011 Level 1 Inputs USD ($) | Sep. 30, 2011 Level 2 Inputs USD ($) | Sep. 30, 2011 Level 2 Inputs USD ($) | Sep. 30, 2011 Level 3 Inputs USD ($) | Sep. 30, 2011 Level 3 Inputs USD ($) | Sep. 30, 2011 Fair Value USD ($) | Sep. 30, 2011 Fair Value USD ($) | Sep. 30, 2011 Fixed income/Interest rate USD ($) | Sep. 30, 2010 Fixed income/Interest rate USD ($) | Sep. 30, 2011 Fixed income/Interest rate USD ($) | Sep. 30, 2010 Fixed income/Interest rate USD ($) | Sep. 30, 2011 Foreign exchange USD ($) | Sep. 30, 2010 Foreign exchange USD ($) | Sep. 30, 2011 Foreign exchange USD ($) | Sep. 30, 2010 Foreign exchange USD ($) | Sep. 30, 2011 Equity USD ($) | Sep. 30, 2010 Equity USD ($) | Sep. 30, 2011 Equity USD ($) | Sep. 30, 2010 Equity USD ($)
Variable annuity reinsurance |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total guarantee value |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 3,000,000,000 | ¥ 234,500,000,000 | $ 2,900,000,000 | ¥ 237,400,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collective account values of underlying variable annuities as a percentage of the guarantee value (as a percent) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 78.00% | 78.00% | 82.00% | 82.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Pre-tax operating results of WM Life Re |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fees, included in other revenues |  |  |  |  | 8,400,000 | 7,700,000 | 24,300,000 | 22,300,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Change in fair value of variable annuity liability, included in other revenues |  |  |  |  |  |  |  |  |  | (164,400,000) | (53,500,000) | (148,000,000) | (204,700,000) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Change in fair value of derivatives, included in other revenues |  |  |  |  | 148,900,000 | (15,700,000) | 105,400,000 | 114,700,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 27,600,000 | 10,800,000 | 75,700,000 | 67,500,000 | 45,600,000 | 27,100,000 | 148,900,000 | 105,400,000 | 29,800,000 | (25,500,000) | 17,300,000 | (1,900,000) | 63,000,000 | 33,000,000 | 32,800,000 | 99,600,000 | 56,100,000 | (23,200,000) | 55,300,000 | 17,000,000
Foreign exchange, included in other revenues |  |  |  |  | 14,800,000 | 10,400,000 | 17,100,000 | 16,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other investment income and gains (losses) |  |  |  |  | 500,000 | (200,000) | (100,000) | (700,000) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total revenues | 501,300,000 | 551,000,000 | 1,584,500,000 | 2,013,900,000 | 8,200,000 | (51,300,000) | (1,300,000) | (52,400,000) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Change in fair value of variable annuity death benefit liabilities, included in other expenses |  |  |  |  |  |  |  |  |  | (5,600,000) | 300,000 | (3,100,000) | (5,800,000) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Death benefit claims paid, included in other expenses |  |  |  |  | (700,000) | (600,000) | (2,400,000) | (1,400,000) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General and administrative expenses | (36,200,000) | (32,100,000) | (120,400,000) | (119,500,000) | (1,100,000) | (1,400,000) | (3,200,000) | (5,000,000) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Pre-tax income (loss) from continuing operations | 1,200,000 | 75,200,000 | 3,600,000 | 57,500,000 | 800,000 | (53,000,000) | (10,000,000) | (64,600,000) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Changes in variable annuity liabilities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Balance of liabilities, at the beginning of the period |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (591,300,000) | (610,200,000) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Realized and unrealized gains (losses) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (170,000,000) | (151,100,000) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Balance of liabilities, at the end of the period |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (761,300,000) | (761,300,000) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Changes in derivative instruments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Balance of assets, at the beginning of the period |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (11,900,000) |  | 48,200,000 | 72,200,000 | 232,700,000 | 275,300,000 | 269,000,000 | 347,500,000 |  |  | 43,900,000 |  |  |  | 225,300,000 |  |  |  | 78,300,000 |
Purchases |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5,000,000 |  | 5,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Realized and unrealized gains (losses) |  |  |  |  | 148,900,000 | (15,700,000) | 105,400,000 | 114,700,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 27,600,000 | 10,800,000 | 75,700,000 | 67,500,000 | 45,600,000 | 27,100,000 | 148,900,000 | 105,400,000 | 29,800,000 | (25,500,000) | 17,300,000 | (1,900,000) | 63,000,000 | 33,000,000 | 32,800,000 | 99,600,000 | 56,100,000 | (23,200,000) | 55,300,000 | 17,000,000
Sales/settlements |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (15,700,000) | (10,800,000) | (48,400,000) | (64,200,000) |  | (29,100,000) | (64,100,000) | (104,100,000) |  |  |  |  |  |  |  |  |  |  |  |
Balance of assets, at the end of the period |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 75,500,000 | 75,500,000 | 278,300,000 | 278,300,000 | 353,800,000 | 353,800,000 | 50,300,000 |  | 50,300,000 |  | 212,000,000 |  | 212,000,000 |  | 91,500,000 |  | 91,500,000 |
Realized and unrealized derivative gains (losses) recognized in other revenues and carrying values of instruments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Realized and unrealized derivative gains (losses) recognized in other revenues |  |  |  |  | 148,900,000 | (15,700,000) | 105,400,000 | 114,700,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 27,600,000 | 10,800,000 | 75,700,000 | 67,500,000 | 45,600,000 | 27,100,000 | 148,900,000 | 105,400,000 | 29,800,000 | (25,500,000) | 17,300,000 | (1,900,000) | 63,000,000 | 33,000,000 | 32,800,000 | 99,600,000 | 56,100,000 | (23,200,000) | 55,300,000 | 17,000,000
Carrying Value |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 75,500,000 | 75,500,000 | 278,300,000 | 278,300,000 | 353,800,000 | 353,800,000 | 50,300,000 |  | 50,300,000 |  | 212,000,000 |  | 212,000,000 |  | 91,500,000 |  | 91,500,000 |
Credit risk on derivative instruments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
OTC derivative instruments |  |  |  |  | 363,400,000 |  | 363,400,000 |  | 351,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collateral held |  |  |  |  | (130,300,000) |  | (130,300,000) |  | (101,000,000) |  |  |  |  |  |  | (58,100,000) | (48,600,000) | (72,200,000) | (52,400,000) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collateral provided |  |  |  |  | 22,600,000 |  | 22,600,000 |  | 25,300,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net exposure to credit losses on fair value of OTC instruments |  |  |  |  | 255,700,000 |  | 255,700,000 |  | 275,800,000 |  |  |  |  |  |  |  |  |  |  | 46,700,000 | 86,500,000 | 49,700,000 | 32,200,000 | 15,600,000 | 14,700,000 | 7,500,000 | 2,800,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of creditworthiness ratings | 21 |  | 21 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Additional collateral |  |  |  |  | 419,700,000 |  | 419,700,000 |  | 326,000,000 |  |  |  |  | 393,300,000 | 291,100,000 | 11,900,000 | 3,300,000 | 14,500,000 | 31,600,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Adjustments for counterparty credit risk |  |  |  |  | $ (9,600,000) |  | $ (9,600,000) |  | $ (4,000,000) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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- Definition Monetary decrease in the future benefit reserve resulting from amounts paid to policy and contract holders during the period for policy benefit claims. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Financial Reporting Release (FRR) -Number 403 -Paragraph 04 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-LHI -Chapter 9 -Paragraph 2, 27 -IssueDate 2006-05-01 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6482485&loc=d3e14764-158437 + Details
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- Definition An amount that an insurer adds to a policy's premium, or deducts from a policy's cash value or contract holder's account, as compensation for services rendered; may include fees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.4) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.13(c)) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 + Details
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- Definition Aggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 5 -Section 03 -Paragraph 1 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1) -URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688 + Details
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- Definition Assets posted as collateral under variable annuity reinsurance trust agreement for the benefit of the reinsurance counterparty. + Details
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- Definition Represents the collective account values of underlying variable annuities as a percentage of the guarantee value of the associated variable annuity reinsurance liability. + Details
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- Definition The amount of collateral that has been posted against amounts owed by counterparties to over the counter derivative instruments against net derivative instrument positions. + Details
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- Definition The amount of collateral held against amounts due to counterparties for over the counter derivative instruments against net derivative instrument positions. + Details
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- Definition Amount by which fair value of over the counter derivatives has been adjusted for counter party credit risk. + Details
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- Definition Purchases that have taken place during the period in relation to derivative assets measured at fair value on a recurring basis. + Details
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- Definition Sales and settlements that have taken place during the period in relation to derivative assets measured at fair value on a recurring basis. + Details
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- Definition This item represents the change in fair value of derivatives due to changes in foreign currency exchange rates, which is included in other revenues. + Details
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- Definition Net increase or decrease in the fair value of the variable annuity death benefit liabilities included in earnings. + Details
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- Definition Net increase or decrease in the fair value of the variable annuity liabilities included in earnings. + Details
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- Definition The net amount as of the balance sheet date of the fair value of derivative assets and derivative liabilities that were not covered by collateral. + Details
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- Definition This item represents other investment income and gains (losses) included in earnings for the period. + Details
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- Definition Total nominal account value guaranteed with certain variable annuities. + Details
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