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

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

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- Definition

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Summary of Significant Accounting Policies - Schedule of Impact of this Adoption (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Line Items]
CECL reserve	$ 124,679	$ 173,549	$ 0
Current expected credit loss reserve	70	1,723	0
Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
CECL reserve			17,650
Current expected credit loss reserve			445
CECL reserve on unfunded loan commitments
Financing Receivable, Allowance for Credit Loss [Line Items]
CECL reserve	6,263	10,031	0
CECL reserve on unfunded loan commitments \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
CECL reserve			3,263
U.S. Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
CECL reserve	26,885	42,995
U.S. Loans \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
CECL reserve			8,955
U.S. Loans \| CECL reserve on unfunded loan commitments
Financing Receivable, Allowance for Credit Loss [Line Items]
CECL reserve	4,072	6,953	0
U.S. Loans \| CECL reserve on unfunded loan commitments \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
CECL reserve			2,801
Non-U.S. Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
CECL reserve	10,263	27,734
Non-U.S. Loans \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
CECL reserve			3,631
Non-U.S. Loans \| CECL reserve on unfunded loan commitments
Financing Receivable, Allowance for Credit Loss [Line Items]
CECL reserve	2,191	2,994	0
Non-U.S. Loans \| CECL reserve on unfunded loan commitments \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
CECL reserve			453
Unique Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
CECL reserve	32,657	33,159	0
Unique Loans \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
CECL reserve			1,356
Unique Loans \| CECL reserve on unfunded loan commitments
Financing Receivable, Allowance for Credit Loss [Line Items]
CECL reserve	$ 0	$ 84	0
Unique Loans \| CECL reserve on unfunded loan commitments \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
CECL reserve			9
CECL reserve on loans \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
CECL reserve			$ 13,942