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Income Taxes Income Taxes - Effective Tax Rates Differing From Prevailing Federal Corporate Income Tax Rates (Details) - Successor [Member] - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Reconciliation of Effective Tax Rates [Line Items] |  |  |  |
Tax on income from continuing operations at statutory rate | $ (99,488) | $ 36,759 | $ 178,521 |
Tax on income from continuing operations at statutory rate,tax rate | 35.00% | 35.00% | 35.00% |
Tax-exempt interest | $ (6,004) | $ (1,561) | $ (1,454) |
Tax-exempt interest, tax rate | 2.10% | (1.50%) | (0.30%) |
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Amortization, Amount | $ 0 | $ 0 | $ 180,079 |
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Amortization, Percent | 0.00% | 0.00% | 35.30% |
Derivative, Gain (Loss) on Derivative, Net | $ (76,257) | $ (545,731) | $ 270,917 |
Valuation allowance | $ 127,675 | $ 139,584 | $ (340,133) |
Valuation allowance, tax rate | (44.90%) | 132.90% | (66.70%) |
Foreign taxes | $ (17,742) | $ 26,183 | $ 288 |
Foreign taxes, tax rate | 6.20% | 24.90% | 0.10% |
Effective Income Tax Rate Reconciliation, Prior Year Income Taxes, Amount | $ 36,124 | $ (171,687) | $ 0 |
Effective Income Tax Rate Reconciliation, Prior Year Income Taxes, Percent | (12.70%) | (163.50%) | 0.00% |
Other, net | $ 2,013 | $ 1,431 | $ 63 |
Other, net, tax rate | (0.70%) | 1.40% | 0.00% |
Income tax expense (benefit) | $ 44,464 | $ 30,709 | $ 17,364 |
Effective Income Tax Rate Reconciliation, Percent | (15.60%) | 29.20% | 3.40% |
Income Tax Reconciliation Tax Bankruptcy Adjustments |  | $ 1,886 | $ 0 | $ 0
Effective income Tax Reconciliation Tax Bankruptcy Adjustments |  | (0.70%) | 0.00% | 0.00%
Financial Services Derivatives Products [Member] | Derivative Products [Member] |  |  |  |
Reconciliation of Effective Tax Rates [Line Items] |  |  |  |
Derivative, Gain (Loss) on Derivative, Net | $ 59,565 | $ (50,273) | $ (42,544) |
Futures Contracts [Member] | Derivative Products [Member] |  |  |  |
Reconciliation of Effective Tax Rates [Line Items] |  |  |  |
Derivative, Gain (Loss) on Derivative, Net | 10,695 | (191) | (1,367) |
Credit Derivatives [Member] | Net Change in Fair Value of Credit Derivatives [Member] |  |  |  |
Reconciliation of Effective Tax Rates [Line Items] |  |  |  |
Derivative, Gain (Loss) on Derivative, Net | 16,372 | 20,106 | 41,701 |
Interest Rate Swaps [Member] | Derivative Products [Member] |  |  |  |
Reconciliation of Effective Tax Rates [Line Items] |  |  |  |
Derivative, Gain (Loss) on Derivative, Net | 48,870 | (50,082) | (41,177) |
Variable Interest Entity, Primary Beneficiary [Member] | Income Loss On Variable Interest Entities [Member] |  |  |  |
Reconciliation of Effective Tax Rates [Line Items] |  |  |  |
Derivative, Gain (Loss) on Derivative, Net | (152,194) | (515,564) | 271,760 |
Variable Interest Entity, Primary Beneficiary [Member] | Currency Swaps [Member] | Income Loss On Variable Interest Entities [Member] |  |  |  |
Reconciliation of Effective Tax Rates [Line Items] |  |  |  |
Derivative, Gain (Loss) on Derivative, Net | (25,530) | 58,990 | 103,757 |
Variable Interest Entity, Primary Beneficiary [Member] | Interest Rate Swaps [Member] | Income Loss On Variable Interest Entities [Member] |  |  |  |
Reconciliation of Effective Tax Rates [Line Items] |  |  |  |
Derivative, Gain (Loss) on Derivative, Net | $ (126,664) | $ (574,554) | $ 168,003 |

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