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

Average fixed interest rate related to the group of interest rate derivatives.

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611

+ Details

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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.

+ Details

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

Reference 2: 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=121590274&loc=SL5579245-113959

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Derivative Instruments and Hedging Activities Schedule of Interest Rate Swaptions (Details) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2020	Dec. 31, 2019	Jun. 30, 2020	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Derivative [Line Items]
Notional	$ 25,836,064,000	$ 48,445,497,000	$ 8,076,933,000	$ 54,226,205,000	$ 55,549,424,000	$ 36,528,169,000
Interest Rate Swaption [Member] \| Long [Member] \| Variable Income Interest Rate [Member] \| Less Than Six Months Remaining Maturity [Member]
Derivative [Line Items]
Cost Basis	(5,780,000)	(24,700,000)
Fair Value	$ 6,942,000	$ 16,095,000
Weighted Average Remaining Maturity	3 months 11 days	3 months 6 days
Interest Rate Swaption [Member] \| Long [Member] \| Fixed Income Interest Rate [Member] \| Less Than Six Months Remaining Maturity [Member]
Derivative [Line Items]
Cost Basis	$ (4,000,000)	$ (4,100,000)
Fair Value	$ 3,849,000	$ 342,000
Weighted Average Remaining Maturity	3 months 11 days	1 month 3 days
Interest Rate Swaption [Member] \| Short [Member] \| Fixed Income Interest Rate [Member] \| Less Than Six Months Remaining Maturity [Member]
Derivative [Line Items]
Cost Basis		$ (20,800,000)
Fair Value		$ 8,636,000
Weighted Average Remaining Maturity		3 months 7 days
Underlying Swap [Member] \| Long [Member] \| Variable Income Interest Rate [Member] \| Less Than Six Months Remaining Maturity [Member]
Derivative [Line Items]
Notional	$ 3,000,000,000	$ 7,525,000,000
Weighted Average Remaining Maturity	10 years	10 years
Underlying Swap [Member] \| Long [Member] \| Variable Income Interest Rate [Member] \| Less Than Six Months Remaining Maturity [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Derivative [Line Items]
Weighted Average Fixed Interest Rate	1.23%	2.27%
Underlying Swap [Member] \| Long [Member] \| Fixed Income Interest Rate [Member] \| Less Than Six Months Remaining Maturity [Member]
Derivative [Line Items]
Notional	$ 3,000,000,000	$ 500,000,000
Weighted Average Remaining Maturity	10 years	10 years
Weighted Average Fixed Interest Rate	0.23%	1.55%
Underlying Swap [Member] \| Short [Member] \| Fixed Income Interest Rate [Member] \| Less Than Six Months Remaining Maturity [Member]
Derivative [Line Items]
Notional		$ 6,768,000,000
Weighted Average Remaining Maturity		10 years
Underlying Swap [Member] \| Short [Member] \| Fixed Income Interest Rate [Member] \| Less Than Six Months Remaining Maturity [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Derivative [Line Items]
Weighted Average Fixed Interest Rate		1.28%