Other Assets and Liabilities - Additional Information (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2021 USD ($) loan	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items]
Current expected credit loss reserve	$ 70	$ 1,723	$ 0
Increase (decrease) in CECL reserve	$ (1,653)	1,278
Number of loans receivable \| loan	118
CECL reserve	$ 124,679	173,549	0
Increase (decrease) in CECL reserve	(48,900)
Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Current expected credit loss reserve			445
Unfunded Loan Commitments
Financing Receivable, Allowance for Credit Loss [Line Items]
Unfunded loan commitments	$ 4,200,000
Number of loans receivable \| loan	118
CECL reserve	$ 6,263	10,031	0
Increase (decrease) in CECL reserve	$ (3,768)	$ 6,768
Unfunded Loan Commitments \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
CECL reserve			$ 3,300

Number of loans in portfolio that contain unfunded commitment balances.

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- Definition

Unfunded Commitments Related To Loans Receivable

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Amount, excluding accrued interest, of allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

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Amount of increase (decrease) in allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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Amount excluding accrued interest, of allowance for credit loss on financing receivable.

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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.

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Amount of increase (decrease) in allowance for credit loss on financing receivable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
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-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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