Derivative Instruments and Hedging Activities Schedule of Total Return Swaps (Details) - USD ($) |
Sep. 30, 2019 |
Jun. 30, 2019 |
Dec. 31, 2018 |
Sep. 30, 2018 |
Jun. 30, 2018 |
Dec. 31, 2017 |
|---|---|---|---|---|---|---|
| Derivative [Line Items] | ||||||
| Notional | $ 54,226,205,000 | $ 55,549,424,000 | $ 36,528,169,000 | $ 41,330,283,000 | $ 28,618,861,000 | $ 31,226,878,000 |
| Markit IOS Total Return Swap [Member] | ||||||
| Derivative [Line Items] | ||||||
| Notional | 43,767,000 | 48,265,000 | ||||
| Fair Value | (13,000) | (383,000) | ||||
| Cost Basis | (59,000) | (59,000) | ||||
| Derivative, Unrealized Gains (Losses) | 46,000 | (324,000) | ||||
| Markit IOS Total Return Swap [Member] | Maturity Date, 1/12/2043 [Member] | ||||||
| Derivative [Line Items] | ||||||
| Notional | 19,439,000 | 21,395,000 | ||||
| Fair Value | (6,000) | (153,000) | ||||
| Cost Basis | (30,000) | (30,000) | ||||
| Derivative, Unrealized Gains (Losses) | 24,000 | (123,000) | ||||
| Markit IOS Total Return Swap [Member] | Maturity Date, 1/12/2044 [Member] | ||||||
| Derivative [Line Items] | ||||||
| Notional | 24,328,000 | 26,870,000 | ||||
| Fair Value | (7,000) | (230,000) | ||||
| Cost Basis | (29,000) | (29,000) | ||||
| Derivative, Unrealized Gains (Losses) | $ 22,000 | $ (201,000) |
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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/disclosureRef
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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 Nominal or face amount used to calculate payment on derivative. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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