Loans Receivable and Allowance for Credit Losses - Summary of Activities in Allowance for loan losses by Portfolio Segments and Unfunded Credit Commitments (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Allowance for unfunded credit reserves
Allowance for unfunded credit commitments, beginning of period			$ 27,500
Allowance for unfunded credit commitments, end of period	$ 24,300		24,300
Provision for (reversal of) credit losses	13,500	$ (15,000)	21,500	$ (15,000)
Unfunded Credit Commitments
Allowance for unfunded credit reserves
Allowance for unfunded credit commitments, beginning of period	23,262	32,529	27,514	33,577
Provision for (reversal of) credit losses on unfunded credit commitments	1,031	(6,210)	(3,221)	(7,261)
Foreign currency translation adjustment	11	(19)	11	(16)
Allowance for unfunded credit commitments, end of period	$ 24,304	$ 26,300	$ 24,304	$ 26,300

Allowance For Unfunded Credit Reserves [Roll Forward]

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- Definition

Reflects the Allowance for Unfunded Credit Commitments

+ References

No definition available.

+ Details

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- Definition

Amount, excluding accrued interest, of foreign currency translation gain (loss) which decreases (increases) allowance for credit loss on financing receivable. Excludes net investment in lease.

+ 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 https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

+ Details

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- Definition

Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ 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)(2)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI https://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585

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