Derivative Instruments - Swaptions (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Interest rate swaps and interest rate swaptions
Fair value of derivative assets	$ 33,675	$ 5,111
Derivative liability, at fair value	43,967	6,370
Derivative instruments not accounted as hedges under GAAP
Interest rate swaps and interest rate swaptions
Fair value of derivative assets	33,675	5,111
Derivative liability, at fair value	43,967	$ 6,370
Interest Rate Swaption \| Fixed Pay Rate \| Derivative instruments not accounted as hedges under GAAP
Interest rate swaps and interest rate swaptions
Fair value of derivative assets	$ 195
Weighted Average Months Until Option Expiration	4 months
Notional amount, assets	$ 50,000
Weighted Average Swap Term (Years)	30 years
Interest Rate Swaption \| Fixed Pay Rate \| Minimum
Interest rate swaps and interest rate swaptions
Derivative, swaption interest rate	1.76%
Interest Rate Swaption \| Fixed Pay Rate \| Maximum
Interest rate swaps and interest rate swaptions
Derivative, swaption interest rate	2.00%
Interest Rate Swaption \| Variable Pay Rate \| Derivative instruments not accounted as hedges under GAAP
Interest rate swaps and interest rate swaptions
Derivative liability, at fair value	$ 14
Weighted Average Months Until Option Expiration	4 months
Notional amount, liabilities	$ (255,000)
Weighted Average Swap Term (Years)	5 years
Interest Rate Swaption \| Variable Pay Rate \| Minimum
Interest rate swaps and interest rate swaptions
Derivative, swaption interest rate	1.26%
Interest Rate Swaption \| Variable Pay Rate \| Maximum
Interest rate swaps and interest rate swaptions
Derivative, swaption interest rate	1.50%

Nominal or face amount used to calculate payments on the derivative asset.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

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- Definition

Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

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- Definition

Nominal or face amount used to calculate payments on the derivative liability.

+ References

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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.

+ References

No definition available.

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- Definition

Fixed interest rate that will be received or paid upon exercise of the interest rate swaption contract.

+ References

No definition available.

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- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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