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Commitments and Contingencies (Narrative) (Details) - USD ($) $ in Thousands		3 Months Ended
	Oct. 19, 2020	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019
Commitments And Contingencies [Line Items]
Allowance for credit loss		$ 49,828	$ 43,356	$ 52,420	$ 30,482
Statute of limitations period	3 years
New York [Member]
Commitments And Contingencies [Line Items]
Statute of limitations period	6 years
Unfunded Commitments [Member]
Commitments And Contingencies [Line Items]
Credit loss expense		(276)	$ 1,000
Unfunded Commitments [Member] | Other Liabilities [Member]
Commitments And Contingencies [Line Items]
Allowance for credit loss		$ 2,900		$ 3,100

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- Definition

Commitments and contingencies.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

+ 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)(1)
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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