Derivative Instruments and Hedging Activities Schedule of Total Return Swaps (Details) - USD ($) |
Mar. 31, 2018 |
Dec. 31, 2017 |
Mar. 31, 2017 |
Dec. 31, 2016 |
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Derivative [Line Items] | ||||
Notional | $ 18,429,288,000 | $ 31,226,878,000 | $ 15,935,535,000 | $ 18,802,500,000 |
Total Return Swap [Member] | ||||
Derivative [Line Items] | ||||
Notional | 61,521,000 | 63,507,000 | ||
Fair Value | (176,000) | (106,000) | ||
Cost Basis | 567,000 | 567,000 | ||
Derivative, Unrealized Gains (Losses) | (743,000) | (673,000) | ||
Total Return Swap [Member] | Maturity Date, 1/12/2043 [Member] | ||||
Derivative [Line Items] | ||||
Notional | 23,607,837 | 24,362,621 | ||
Fair Value | (63,000) | (24,000) | ||
Cost Basis | 201,000 | 201,000 | ||
Derivative, Unrealized Gains (Losses) | (264,000) | (225,000) | ||
Total Return Swap [Member] | Maturity Date, 1/12/2044 [Member] | ||||
Derivative [Line Items] | ||||
Notional | 37,913,368 | 39,144,706 | ||
Fair Value | (113,000) | (82,000) | ||
Cost Basis | 366,000 | 366,000 | ||
Derivative, Unrealized Gains (Losses) | $ (479,000) | $ (448,000) |
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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Cost (or upfront payable/receivable) as of the balance sheet date of the derivative or group of derivatives. No definition available.
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- Definition The aggregate net gain (loss) from increase (decrease) in fair value of derivatives. No definition available.
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- Definition Fair value of the assets less the liabilities of a derivative or group of derivatives. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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