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Income Taxes (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2016 | Sep. 30, 2015 | Dec. 31, 2007 | Dec. 31, 2015 | Dec. 31, 2014
Valuation Allowance [Line Items] |  |  |  |  |  |  |
Number of years used in the cumulative income position calculation |  |  | 3 years |  |  |  |
Provision for income tax | $ 27,131 | $ 43,694 | $ 117,646 | $ 131,568 |  |  |
Change in valuation allowance | 0 | (739,298) | 0 | (822,465) |  |  |
Provision for (benefit from) income taxes | 27,131 | (695,604) | 117,646 | (690,897) |  |  |
Net operating loss carryforwards, regular tax basis | 1,600,000 |  | 1,600,000 |  |  |  |
Net operating loss carryforwards for computing the alternative minimum tax | 700,000 |  | 700,000 |  |  |  |
Information regarding income tax examinations [Abstract] |  |  |  |  |  |  |
Amount of IRS assessment for unpaid taxes and penalties related to REMIC issue |  |  |  |  |  |  | $ 197,500
Estimate of federal interest that may be due | 195,900 |  | 195,900 |  |  |  |
Amount of payment made related to the IRS assessment on the REMIC issue |  |  |  |  | $ 65,200 |  |
Amount of IRS assessment for unpaid taxes and penalties related to disallowance of carryback of 2009 net operating loss |  |  |  |  |  |  | $ 261,400
Estimate of additional state income taxes and interest that may be due | 50,200 |  | 50,200 |  |  |  |
Total amount of unrecognized tax benefits | 107,900 |  | 107,900 |  |  |  |
Total amount of the unrecognized tax benefits that would affect our effective tax rate | 94,400 |  | 94,400 |  |  |  |
Unrecognized tax benefits, accrued interest | $ 28,600 |  | $ 28,600 |  |  | $ 27,800 |
Other Comprehensive Income (Loss) |  |  |  |  |  |  |
Valuation Allowance [Line Items] |  |  |  |  |  |  |
Change in valuation allowance |  | $ 70,000 |  | $ 54,500 |  |  |

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- Definition The amount of the IRS assessment for unpaid taxes and penalties related to the REMIC issue. + References No definition available. + Details
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- Definition The amount of the IRS assessment for unpaid taxes and penalties related to the disallowance of the carryback of the 2009 net operating loss. + References No definition available. + Details
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- Definition The number of years used by the entity in the calculation of its cumulative income position + References No definition available. + Details
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- Definition The estimate of additional state income taxes and interest that may be due upon the resolution of the REMIC issue. + References No definition available. + Details
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- Definition The sum of the current income tax expense or benefit and the deferred income tax expense or benefit, excluding the change in the deferred tax valuation allowance, pertaining to pretax income or loss from continuing operations. + References No definition available. + Details
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- Definition The sum of domestic, foreign and state and local operating loss carryforwards, before tax effects, available to reduce future taxable income under enacted tax laws and used for computing the alternative minimum tax. + References No definition available. + Details
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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a),(b) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32639-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Income Tax Expense (or Benefit) -URI http://asc.fasb.org/extlink&oid=6515339 + Details
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