Other Assets and Liabilities - Additional Information (Detail)	3 Months Ended
Mar. 31, 2022 USD ($) loan	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items]
Increase (decrease) in CECL reserve	$ (70,000)	$ (834,000)
Current expected credit loss reserve	0	889,000	$ 70,000	$ 1,723,000
Increase (decrease) in CECL reserve	(2,500,000)	(1,400,000)
CECL reserve	122,221,000	172,100,000	124,679,000	173,549,000
Unfunded Loan Commitments
Financing Receivable, Allowance for Credit Loss [Line Items]
Unfunded loan commitments	$ 4,500,000,000
Number of loans receivable \| loan	126
Increase (decrease) in CECL reserve	$ (9,000)	990,000
CECL reserve	$ 6,254,000	$ 11,021,000	$ 6,263,000	$ 10,031,000

Number of loans in portfolio that contain unfunded commitment balances.

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- Definition

Unfunded Commitments Related To Loans Receivable

+ References

No definition available.

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- Definition

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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- Definition

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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- Definition

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

+ 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.

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No definition available.

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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
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

Reference 2: 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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