Reconciliation of Total Segments to Income (loss) Before Provision for Taxes and Total Assets (Detail) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | ||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Sep. 30, 2015 |
Sep. 30, 2014 |
Sep. 30, 2015 |
Sep. 30, 2014 |
Dec. 31, 2014 |
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| Segment Reporting Information [Line Items] | ||||||||||||||||||||||||||
| Revenues | $ 11,573 | $ 1,679,426 | $ 3,749,133 | $ 5,463,954 | ||||||||||||||||||||||
| Expenses | 476,997 | 1,055,138 | 2,533,997 | 3,032,770 | ||||||||||||||||||||||
| Other Income | (16,867) | 8,682 | 158,703 | 217,422 | ||||||||||||||||||||||
| Income (Loss) Before Provision (Benefit) for Taxes | (482,291) | 632,970 | 1,373,839 | 2,648,606 | ||||||||||||||||||||||
| Total Assets | 23,618,703 | 23,618,703 | $ 31,497,097 | |||||||||||||||||||||||
| Operating Segments | ||||||||||||||||||||||||||
| Segment Reporting Information [Line Items] | ||||||||||||||||||||||||||
| Revenues | (32,195) | 1,653,903 | 3,678,745 | 5,399,681 | ||||||||||||||||||||||
| Expenses | 356,661 | 816,028 | 1,906,791 | 2,385,565 | ||||||||||||||||||||||
| Income (Loss) Before Provision (Benefit) for Taxes | (388,856) | 837,875 | 1,771,954 | 3,014,116 | ||||||||||||||||||||||
| Total Assets | 18,638,064 | 18,638,064 | ||||||||||||||||||||||||
| Consolidation Adjustments and Reconciling Items | ||||||||||||||||||||||||||
| Segment Reporting Information [Line Items] | ||||||||||||||||||||||||||
| Revenues | 43,768 | [1] | 25,523 | [1] | 70,388 | [2] | 64,273 | [2] | ||||||||||||||||||
| Expenses | [3] | 120,336 | 239,110 | 627,206 | 647,205 | |||||||||||||||||||||
| Other Income | (16,867) | [4] | 8,682 | [4] | 158,703 | [5] | 217,422 | [5] | ||||||||||||||||||
| Income (Loss) Before Provision (Benefit) for Taxes | (93,435) | [6] | $ (204,905) | [6] | (398,115) | [7] | $ (365,510) | [7] | ||||||||||||||||||
| Total Assets | [8] | $ 4,980,639 | $ 4,980,639 | |||||||||||||||||||||||
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