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Amount of increase in allowance for credit loss on financing receivable from recovery.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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Loans and Leases Receivable and Allowance for Credit Losses on Loans and Leases - Schedule of Allowance for Credit Losses (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance				$ 144,176				$ 56,379	$ 144,176	$ 56,379
Charge-offs									(40,381)	(61,736)
Recoveries									6,583	6,930
Provision for credit losses on loans and leases	$ 13,890	$ 13,164	$ 3,291	(2,919)	$ (2,913)	$ 12,955	$ 20,946	31,786	27,426	62,774	$ 24,227
Ending balance	137,804				144,176				137,804	144,176	56,379
Multi-family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance				12,620				6,157	12,620	6,157
Charge-offs									(1,132)	0
Recoveries									0	0
Provision for credit losses on loans and leases									(7,011)	4,292
Ending balance	4,477				12,620				4,477	12,620	6,157
Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance				12,239				15,556	12,239	15,556
Charge-offs									(1,550)	(3,158)
Recoveries									1,102	3,019
Provision for credit losses on loans and leases									911	(3,937)
Ending balance	12,702				12,239				12,702	12,239	15,556
Commercial real estate owner occupied
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance				9,512				2,235	9,512	2,235
Charge-offs									(749)	(78)
Recoveries									500	28
Provision for credit losses on loans and leases									(6,050)	1,554
Ending balance	3,213				9,512				3,213	9,512	2,235
Commercial real estate non-owner occupied
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance				19,452				6,243	19,452	6,243
Charge-offs									(944)	(25,779)
Recoveries									84	1,293
Provision for credit losses on loans and leases									(12,382)	29,777
Ending balance	6,210				19,452				6,210	19,452	6,243
Construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance				5,871				1,262	5,871	1,262
Charge-offs									0	0
Recoveries									125	128
Provision for credit losses on loans and leases									(5,304)	4,579
Ending balance	692				5,871				692	5,871	1,262
Residential real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance				3,977				3,218	3,977	3,218
Charge-offs									(130)	(60)
Recoveries									54	86
Provision for credit losses on loans and leases									(1,518)	(785)
Ending balance	2,383				3,977				2,383	3,977	3,218
Manufactured housing
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance				5,190				1,060	5,190	1,060
Charge-offs									0	0
Recoveries									0	0
Provision for credit losses on loans and leases									(912)	328
Ending balance	4,278				5,190				4,278	5,190	1,060
Installment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance				$ 75,315				20,648	75,315	20,648
Charge-offs									(35,876)	(32,661)
Recoveries									4,718	2,376
Provision for credit losses on loans and leases									59,692	26,966
Ending balance	$ 103,849				$ 75,315				$ 103,849	75,315	20,648
Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance								79,829		79,829
Ending balance											79,829
Cumulative Effect, Period of Adoption, Adjustment \| Multi-family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance								2,171		2,171
Ending balance											2,171
Cumulative Effect, Period of Adoption, Adjustment \| Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance								759		759
Ending balance											759
Cumulative Effect, Period of Adoption, Adjustment \| Commercial real estate owner occupied
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance								5,773		5,773
Ending balance											5,773
Cumulative Effect, Period of Adoption, Adjustment \| Commercial real estate non-owner occupied
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance								7,918		7,918
Ending balance											7,918
Cumulative Effect, Period of Adoption, Adjustment \| Construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance								(98)		(98)
Ending balance											(98)
Cumulative Effect, Period of Adoption, Adjustment \| Residential real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance								1,518		1,518
Ending balance											1,518
Cumulative Effect, Period of Adoption, Adjustment \| Manufactured housing
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance								3,802		3,802
Ending balance											3,802
Cumulative Effect, Period of Adoption, Adjustment \| Installment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance								$ 57,986		$ 57,986
Ending balance											$ 57,986