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Fair Value Measurements - Summary of Changes in Level 3 Fair Value Category (Detail) - Successor [Member] - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2015 | Sep. 30, 2014 | Sep. 30, 2015 | Sep. 30, 2014
Investment by Class [Member] |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, beginning of period | $ 380,332 | $ 66,352 | $ 198,201 | $ 67,783
Additions of VIEs consolidated |  |  | 0 | 0
Included in earnings | 8,429 | 835 | 21,066 | 1,676
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss | (4,288) | (254) | (48,611) | (595)
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Purchases | 28 |  | 234,880 |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Sales |  | (3,388) |  | (3,388)
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Settlements | (712) | (885) | (21,747) | (2,608)
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Into Level Three | 0 | 0 | 0 | 0
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Out Of Level Three |  |  |  | (208)
Balance, end of period | 383,789 | 62,660 | 383,789 | 62,660
Derivatives by Class [Member] |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, beginning of period | (119,309) | (218,661) | (215,346) | (186,934)
Included in earnings | 20,073 | 3,885 | 20,640 | (36,323)
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 | (2,822) | (1,126) | 4,430 | 7,355
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Into Level Three | 0 | 0 | 88,218 | 0
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Out Of Level Three | 0 | 0 | 0 | 0
Balance, end of period | (102,058) | (215,902) | (102,058) | (215,902)
The amount of total gains/(losses) included in earnings attributable to the change in unrealized gains or losses relating to assets and liabilities still held at the reporting date | 12,285 | (3,229) | 20,081 | 39,830
Credit Derivative [Member] | Derivatives by Class [Member] |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, beginning of period | (66,490) | (89,651) | (73,459) | (94,322)
Included in earnings | 36,952 | 7,417 | 44,746 | 13,580
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 | (349) | (596) | (1,174) | (2,088)
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Into Level Three | 0 | 0 | 0 | 0
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Out Of Level Three | 0 | 0 | 0 | 0
Balance, end of period | (29,887) | (82,830) | (29,887) | (82,830)
The amount of total gains/(losses) included in earnings attributable to the change in unrealized gains or losses relating to assets and liabilities still held at the reporting date | (4,594) | (6,761) | (4,025) | (10,073)
Interest Rate Swaps [Member] | Derivatives by Class [Member] |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, beginning of period | (52,819) | (129,010) | (141,887) | (92,612)
Included in earnings | (16,879) | (3,532) | (24,106) | (49,903)
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 | (2,473) | (530) | 5,604 | 9,443
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Into Level Three | 0 | 0 | 88,218 | 0
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Out Of Level Three | 0 | 0 | 0 | 0
Balance, end of period | (72,171) | (133,072) | (72,171) | (133,072)
The amount of total gains/(losses) included in earnings attributable to the change in unrealized gains or losses relating to assets and liabilities still held at the reporting date | 16,879 | 3,532 | 24,106 | 49,903
Residential Mortgage-Backed Securities [Member] | Investment by Class [Member] |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, beginning of period | 380,332 | 0 | 194,393 | 0
Additions of VIEs consolidated |  |  | 0 | 0
Included in earnings | 8,429 | 0 | 21,085 | 0
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss | (4,288) |  | (48,325) |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Purchases | 28 |  | 234,880 |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Settlements | (712) | 0 | (18,244) | 0
Balance, end of period | 383,789 |  | 383,789 |
Asset-backed Securities [Member] | Investment by Class [Member] |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, beginning of period | 0 | 62,601 | 0 | 64,073
Additions of VIEs consolidated |  |  | 0 | 0
Included in earnings | 0 | 859 | 0 | 1,748
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss | 0 | (272) | 0 | (910)
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Sales |  | (3,388) |  | (3,388)
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Settlements | 0 | (885) | 0 | (2,608)
Balance, end of period | 0 | 58,915 | 0 | 58,915
Corporate Obligations [Member] | Investment by Class [Member] |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, beginning of period | 0 | 3,751 | 3,808 | 3,502
Additions of VIEs consolidated |  |  | 0 | 0
Included in earnings | 0 | (24) | (19) | (72)
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss | 0 | 18 | (286) | 315
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Settlements |  |  | (3,503) |
Balance, end of period | 0 | 3,745 | 0 | 3,745
US Government Agencies Debt Securities [Member] | Investment by Class [Member] |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, beginning of period | 0 | 0 | 0 | 208
Additions of VIEs consolidated |  |  | 0 | 0
Included in earnings | 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 Out Of Level Three |  |  |  | (208)
Level 3 [Member] |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, beginning of period | 13,856,298 | 14,917,043 | 13,845,454 | 14,253,705
Included in earnings | 52,394 | 301,522 | (166,100) | 666,194
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss | (503,211) | (758,705) | (402,726) | (305,933)
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Purchases | 28 | 0 | 234,880 | 70,000
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 | 3,388 | 0 | 3,388
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Settlements | 69,909 | 70,951 | 264,126 | 294,849
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Into Level Three | 0 | 0 | 88,218 | 0
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Out Of Level Three |  | 659,898 |  | 660,106
Deconsolidation of VIEs | 325,123 |  | 325,123 |
Balance, end of period | 13,010,477 | 13,725,623 | 13,010,477 | 13,725,623
The amount of total gains/(losses) included in earnings attributable to the change in unrealized gains or losses relating to assets and liabilities still held at the reporting date | (22,297) | (307,213) | 217,197 | (666,198)
Level 3 [Member] | Derivative Financial Instruments, Liabilities [Member] |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, beginning of period | (119,309) | (218,661) | (215,346) | (186,934)
Included in earnings | 20,073 | 3,885 | 20,640 | (36,323)
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 | 2,822 | 1,126 | (4,430) | (7,355)
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Into Level Three | 0 | 0 | 88,218 | 0
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Out Of Level Three | 0 | 0 | 0 | 0
Deconsolidation of VIEs | 0 |  | 0 |
Balance, end of period | (102,058) | (215,902) | (102,058) | (215,902)
The amount of total gains/(losses) included in earnings attributable to the change in unrealized gains or losses relating to assets and liabilities still held at the reporting date | 12,285 | (3,229) | 20,081 | 39,830
Level 3 [Member] | Investments [Member] |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, beginning of period | 380,332 | 66,352 | 198,201 | 67,783
Included in earnings | 8,429 | 835 | 21,066 | 1,676
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss | (4,288) | (254) | (48,611) | (595)
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Purchases | 28 | 0 | 234,880 | 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 | 3,388 | 0 | 3,388
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Settlements | 712 | 885 | 21,747 | 2,608
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Into Level Three | 0 | 0 | 0 | 0
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Out Of Level Three | 0 | 0 | 0 | 208
Deconsolidation of VIEs | 0 |  | 0 |
Balance, end of period | 383,789 | 62,660 | 383,789 | 62,660
The amount of total gains/(losses) included in earnings attributable to the change in unrealized gains or losses relating to assets and liabilities still held at the reporting date | 0 | 0 | 0 | 0
Level 3 [Member] | Other Assets [Member] |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, beginning of period | 9,704 | 12,782 | 12,036 | 13,384
Included in earnings | (382) | (381) | (1,009) | (983)
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 | 1,705 | 0
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Into Level Three | 0 | 0 | 0 | 0
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Out Of Level Three | 0 | 0 | 0 | 0
Deconsolidation of VIEs |  |  | 0 |
Balance, end of period | 9,322 | 12,401 | 9,322 | 12,401
The amount of total gains/(losses) included in earnings attributable to the change in unrealized gains or losses relating to assets and liabilities still held at the reporting date | 382 | 381 | 1,009 | 983
Variable Interest Entity, Primary Beneficiary [Member] |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
The amount of total gains/(losses) included in earnings attributable to the change in unrealized gains or losses relating to assets and liabilities still held at the reporting date |  |  | 196,107 | (707,011)
Variable Interest Entity, Primary Beneficiary [Member] | Level 3 [Member] | Long-Term Debt [Member] |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, beginning of period | (2,166,826) | (1,375,049) | (1,263,664) | (1,514,605)
Included in earnings | (59,760) | (16,961) | (922,849) | (268,951)
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss | 79,314 | 62,314 | 35,303 | 24,066
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 | (3,740) | (4,102) | (7,678) | (433,896)
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Into Level Three | 0 | 0 | 0 | 0
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Out Of Level Three |  | (36,891) | 0 | (36,891)
Deconsolidation of VIEs | 0 |  | 0 |
Balance, end of period | (2,143,532) | (1,288,703) | (2,143,532) | (1,288,703)
The amount of total gains/(losses) included in earnings attributable to the change in unrealized gains or losses relating to assets and liabilities still held at the reporting date | 107,567 | 16,047 | 970,656 | 264,899
Variable Interest Entity, Primary Beneficiary [Member] | Level 3 [Member] | Loans Receivable [Member] |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, beginning of period | 13,005,216 | 13,743,231 | 12,371,177 | 13,398,895
Included in earnings | 44,404 | 209,028 | 701,562 | 735,597
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss | (471,321) | (678,944) | (311,773) | (270,727)
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Purchases | 0 | 0 | 0 | 70,000
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 | 70,115 | 73,042 | 252,782 | 733,492
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Into Level Three | 0 | 0 | 0 | 0
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Out Of Level Three |  | 696,789 |  | 696,789
Deconsolidation of VIEs | 325,123 |  | 325,123 |
Balance, end of period | 12,183,061 | 12,503,484 | 12,183,061 | 12,503,484
The amount of total gains/(losses) included in earnings attributable to the change in unrealized gains or losses relating to assets and liabilities still held at the reporting date | (102,901) | (215,296) | (760,059) | (736,732)
Variable Interest Entity, Primary Beneficiary [Member] | Level 3 [Member] | Corporate Obligations [Member] |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, beginning of period | 2,747,181 | 2,688,388 | 2,743,050 | 2,475,182
Included in earnings | 39,630 | 105,116 | 14,490 | 235,178
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss | (106,916) | (141,821) | (77,645) | (58,677)
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 | 0 | 0
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Transfers Out Of Level Three | 0 | 0 | 0 | 0
Deconsolidation of VIEs | 0 |  | 0 |
Balance, end of period | 2,679,895 | 2,651,683 | 2,679,895 | 2,651,683
The amount of total gains/(losses) included in earnings attributable to the change in unrealized gains or losses relating to assets and liabilities still held at the reporting date | $ (39,630) | $ (105,116) | $ (14,490) | $ (235,178)

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