Repurchase Agreements (Details) - USD ($) $ in Thousands |
3 Months Ended | 12 Months Ended |
|---|---|---|
Mar. 31, 2018 |
Dec. 31, 2017 |
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| Disclosure of Repurchase Agreements [Abstract] | ||
| Repurchase agreements | $ 19,148,679 | $ 19,451,207 |
| Weighted average borrowing rate | 1.96% | 1.69% |
| Weighted average remaining maturity | 97 days | 83 days |
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- Definition Weighted average maturity (weighted by amount of the agreements) of repurchase agreements. No definition available.
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- Definition Interest rate on the amount to be repaid to the counterparty to the repurchase agreement when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under the repurchase agreement exceeds 10 percent of total assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount to be repaid to the counterparty to the repurchase agreement when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under the repurchase agreement exceeds 10 percent of total assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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