Summary of Significant Accounting Principles - Change in Accounting Estimate (Details) - Nonrefundable Fees and Other Costs, Prepayment Method - USD ($) $ / shares in Units, $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
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| Change in Accounting Estimate [Line Items] | |||
| Increase (decrease) in net interest income | $ (141) | $ 989 | |
| Increase (decrease) in gains on sales of debt securities | 47 | 127 | |
| Increase (decrease) in net income | $ (52) | $ 687 | |
| Increase (decrease) in earnings per diluted share (in dollars per share) | $ 0.00 | $ 0.06 | |
| Cumulative effect of change in retained earnings | $ (980) | ||
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- Definition New Accounting Pronouncement or Change in Accounting Principal, Effect of Change on Marketable Securities, Realized Gain (Loss), Excluding Other than Temporary Impairments No definition available.
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- Definition New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Interest and Dividend Income, Operating No definition available.
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of the effect of a change in accounting principle on diluted earnings per share. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of the effect of a change in accounting principle on net income. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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