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Derivative Financial Instruments - Schedule of Floor Spread Transactions Designated as Cash Flow Hedges (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Derivative Instruments, Gain (Loss) [Line Items]
Notional amounts	$ 1,452,000,000	$ 665,500,000
Interest Rate Floor | Cash Flow Hedging | Derivatives designated as hedging instruments
Derivative Instruments, Gain (Loss) [Line Items]
Notional amounts	$ 100,000,000	$ 210,000,000
Weighted average floor strike rate	0.75%	2.00%
Weighted average sold floor rate		1.00%
Weighted average rates	0.15%	1.70%
Weighted average maturity (in years)	2 years 3 months 18 days	2 years 1 month 6 days
Unrealized gains (losses)	$ 1,392,000	$ 1,820,000

X

- Definition

Derivative average interest rate.

+ References

No definition available.

+ Details

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X

- Definition

Weighted average sold floor rate.

+ References

No definition available.

+ Details

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X

- Definition

Average floor rate on a group of interest rate derivatives, such as interest rate floor or collars. If market rates fall below the floor rate, a payment or receipt is triggered on the contract.

+ References

No definition available.

+ Details

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X

- 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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X

- 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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X

- 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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X

- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

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- Details

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- Details

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