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	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 156,530	$ 125,436	$ 137,804	$ 144,176
Charge-offs	(21,484)	(8,755)	(45,935)	(31,361)
Recoveries	2,987	1,651	6,731	5,145
Provision (benefit) for credit losses on loans and leases	(7,836)	13,164	31,597	13,536
Ending balance	130,197	131,496	130,197	131,496
Commercial and industrial, including specialty lending
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	11,081	8,127	12,702	12,239
Charge-offs	(2,657)	(516)	(3,235)	(1,153)
Recoveries	76	400	1,129	945
Provision (benefit) for credit losses on loans and leases	6,631	2,849	4,535	(1,171)
Ending balance	15,131	10,860	15,131	10,860
Multi-family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	9,765	5,028	4,477	12,620
Charge-offs	0	0	(1,990)	(1,132)
Recoveries	0	0	337	0
Provision (benefit) for credit losses on loans and leases	4,479	(631)	11,420	(7,091)
Ending balance	14,244	4,397	14,244	4,397
Commercial real estate owner occupied
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	4,745	4,464	3,213	9,512
Charge-offs	0	(524)	0	(666)
Recoveries	0	474	49	483
Provision (benefit) for credit losses on loans and leases	1,475	(797)	2,958	(5,712)
Ending balance	6,220	3,617	6,220	3,617
Commercial real estate non-owner occupied
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	8,880	7,374	6,210	19,452
Charge-offs	(4,862)	(943)	(5,025)	(943)
Recoveries	31	0	43	69
Provision (benefit) for credit losses on loans and leases	7,283	944	10,104	(11,203)
Ending balance	11,332	7,375	11,332	7,375
Construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,179	2,643	692	5,871
Charge-offs	0	0	0	0
Recoveries	10	3	226	122
Provision (benefit) for credit losses on loans and leases	425	(1,760)	696	(5,107)
Ending balance	1,614	886	1,614	886
Residential real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	5,578	2,299	2,383	3,977
Charge-offs	0	(79)	(4)	(129)
Recoveries	13	25	58	47
Provision (benefit) for credit losses on loans and leases	(138)	(333)	3,016	(1,983)
Ending balance	5,453	1,912	5,453	1,912
Manufactured housing
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	4,080	4,372	4,278	5,190
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision (benefit) for credit losses on loans and leases	402	38	204	(780)
Ending balance	4,482	4,410	4,482	4,410
Installment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	111,222	91,129	103,849	75,315
Charge-offs	(13,965)	(6,693)	(35,681)	(27,338)
Recoveries	2,857	749	4,889	3,479
Provision (benefit) for credit losses on loans and leases	(28,393)	12,854	(1,336)	46,583
Ending balance	$ 71,721	$ 98,039	$ 71,721	$ 98,039

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

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Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

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

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Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

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

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ 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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