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Fair Value Measurements - Information about Valuation Inputs for Variable Interest Entity Assets and Liabilities Classified as Level 3 (Detail) - Successor [Member] - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |  |  |  |
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Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2016 | Sep. 30, 2015 | Jun. 30, 2016 | Dec. 31, 2015 | Jun. 30, 2015 | Dec. 31, 2014
Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability | $ 12,363,248 | $ 13,010,477 | $ 12,363,248 | $ 13,010,477 | $ 12,021,381 | $ 11,497,098 | $ 13,856,298 | $ 13,845,454
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Earnings | 622,065 | 52,394 | 1,244,712 | (166,100) |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss | (216,229) | (503,211) | (1,326,847) | (402,726) |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Purchases | 7,126 | 28 | 99,018 | 234,880 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Issues | 0 | 0 | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Sales | 0 | 0 | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Settlements | 71,095 | 69,909 | (10,571) | 264,126 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Into Level Three |  |  | 100,798 | 88,218 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Out Of Level Three |  |  | (737,898) |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Deconsolidation Of Vies |  | 325,123 |  | 325,123 |  |  |  |
Fair Value Asset Or Liability Measured On Recurring Basis Change In Unrealized Gains Losses Still Held | 606,031 | 22,297 | 1,201,113 | (217,197) |  |  |  |
Fair Value, Inputs, Level 3 [Member] | Investments [Member] |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability | 752,474 | 383,789 | 752,474 | 383,789 | 722,670 | 488,884 | 380,332 | 198,201
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Earnings | 15,804 | 8,429 | 42,823 | 21,066 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss | 12,334 | (4,288) | 35,570 | (48,611) |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Purchases | 7,126 | 28 | 99,018 | 234,880 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Issues | 0 | 0 | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Sales | 0 | 0 | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Settlements | 5,460 | 712 | 14,619 | 21,747 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Into Level Three |  |  | 100,798 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Out Of Level Three |  |  | 0 |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Deconsolidation Of Vies |  | 0 |  | 0 |  |  |  |
Fair Value Asset Or Liability Measured On Recurring Basis Change In Unrealized Gains Losses Still Held |  | 0 | 0 | 0 |  |  |  |
Fair Value, Inputs, Level 3 [Member] | European ABS Transactions [Member] |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |  |  |  |  |  |  |
Fair Value Of Consolidated Variable Interest Entity Debt Obligations Valued Using Unobservable Inputs By Asset Class | 2,552,212 |  | 2,552,212 |  |  | 3,016,966 |  |
Fair Value, Inputs, Level 3 [Member] | US Commercial ABS Transaction [Member] |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |  |  |  |  |  |  |
Fair Value Of Consolidated Variable Interest Entity Debt Obligations Valued Using Unobservable Inputs By Asset Class | 31,088 |  | 31,088 |  |  | 163,204 |  |
Fair Value, Inputs, Level 3 [Member] | Other Assets [Member] |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability | 7,729 | 9,322 | 7,729 | 9,322 | 8,687 | 8,696 | 9,704 | 12,036
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Earnings | (958) | (382) | (967) | (1,009) |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss | 0 | 0 | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Purchases | 0 | 0 | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Issues | 0 | 0 | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Sales | 0 | 0 | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Settlements | 0 | 0 | 0 | 1,705 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Into Level Three |  |  | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Out Of Level Three |  |  | 0 |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Deconsolidation Of Vies |  | 0 |  | 0 |  |  |  |
Fair Value Asset Or Liability Measured On Recurring Basis Change In Unrealized Gains Losses Still Held | (958) | (382) | (967) | (1,009) |  |  |  |
Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Liabilities [Member] |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability |  | (102,058) |  | (102,058) |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Deconsolidation Of Vies |  | 0 |  |  |  |  |  |
Fair Value, Inputs, Level 3 [Member] | Loans Receivable [Member] |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability | 11,476,766 |  | 11,476,766 |  |  |  |  |
Loan Origination Commitments [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability |  | 12,183,061 |  | 12,183,061 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Deconsolidation Of Vies |  | 325,123 |  |  |  |  |  |
Long-term Debt [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability | (2,583,300) | (2,143,532) | (2,583,300) | (2,143,532) |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Deconsolidation Of Vies |  | 0 |  |  |  |  |  |
Derivative Financial Instruments, Liabilities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability | (119,106) | (102,058) | (119,106) | (102,058) | (104,032) | (99,192) | (119,309) | (215,346)
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Earnings | (12,220) | 20,073 | (23,250) | 20,640 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss | 0 | 0 | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Purchases | 0 | 0 | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Issues | 0 | 0 | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Sales | 0 | 0 | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Settlements | 2,854 | 2,822 | (3,336) | (4,430) |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Into Level Three |  |  | 0 | 88,218 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Out Of Level Three |  |  | 0 |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Deconsolidation Of Vies |  |  |  | 0 |  |  |  |
Fair Value Asset Or Liability Measured On Recurring Basis Change In Unrealized Gains Losses Still Held | (12,450) | (12,285) | (24,026) | (20,081) |  |  |  |
Investment Contracts [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability |  | 2,679,895 |  | 2,679,895 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Deconsolidation Of Vies |  | 0 |  |  |  |  |  |
Variable Interest Entity, Primary Beneficiary [Member] |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |  |  |  |  |  |  |
Fair Value Asset Or Liability Measured On Recurring Basis Change In Unrealized Gains Losses Still Held |  |  | 1,226,106 | (196,107) |  |  |  |
Variable Interest Entity, Primary Beneficiary [Member] | Fair Value, Inputs, Level 3 [Member] | Loans Receivable [Member] |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability | 11,476,766 | 12,183,061 | 11,476,766 | 12,183,061 | 11,074,772 | 11,690,324 | 13,005,216 | 12,371,177
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Earnings | 690,431 | 44,404 | 1,367,063 | 701,562 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss | (221,934) | (471,321) | (1,385,893) | (311,773) |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Purchases | 0 | 0 | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Issues | 0 | 0 | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Sales | 0 | 0 | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Settlements | 66,503 | 70,115 | 194,728 | 252,782 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Into Level Three |  |  | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Out Of Level Three |  |  | 0 |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Deconsolidation Of Vies |  |  |  | 325,123 |  |  |  |
Fair Value Asset Or Liability Measured On Recurring Basis Change In Unrealized Gains Losses Still Held | 690,431 | 102,901 | 1,367,063 | 760,059 |  |  |  |
Variable Interest Entity, Primary Beneficiary [Member] | Fair Value, Inputs, Level 3 [Member] | Corporate Debt Securities [Member] |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability | 2,828,685 | 2,679,895 | 2,828,685 | 2,679,895 | 2,577,293 | 2,588,556 | 2,747,181 | 2,743,050
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Earnings | 307,147 | 39,630 | 571,739 | 14,490 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss | (55,755) | (106,916) | (331,610) | (77,645) |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Purchases | 0 | 0 | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Issues | 0 | 0 | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Sales | 0 | 0 | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Settlements | 0 | 0 | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Into Level Three |  |  | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Out Of Level Three |  |  | 0 |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Deconsolidation Of Vies |  |  |  | 0 |  |  |  |
Fair Value Asset Or Liability Measured On Recurring Basis Change In Unrealized Gains Losses Still Held | 307,147 | 39,630 | 571,739 | 14,490 |  |  |  |
Variable Interest Entity, Primary Beneficiary [Member] | Long-term Debt [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability | (2,583,300) | (2,143,532) | (2,583,300) | (2,143,532) | $ (2,258,009) | $ (3,180,170) | $ (2,166,826) | $ (1,263,664)
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Earnings | (378,139) | (59,760) | (712,696) | (922,849) |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss | 49,126 | 79,314 | 355,086 | 35,303 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Purchases | 0 | 0 | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Issues | 0 | 0 | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Sales | 0 | 0 | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Settlements | (3,722) | (3,740) | (216,582) | (7,678) |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Into Level Three |  |  | 0 | 0 |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Out Of Level Three |  |  | (737,898) |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Deconsolidation Of Vies |  |  |  | 0 |  |  |  |
Fair Value Asset Or Liability Measured On Recurring Basis Change In Unrealized Gains Losses Still Held | $ (378,139) | $ (107,567) | $ (712,696) | $ (970,656) |  |  |  |

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- Definition The amount of gains or losses included in earnings attributable to unrealized gains or losses on financial instruments measured on a recurring basis using unobservable inputs that are still held at the reporting date. + References No definition available. + Details
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- Definition Amount of gain or loss included in earnings arising from financial instruments measured on a recurring basis using unobservable inputs. + References No definition available. + Details
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