Loans and Leases Held for Investment at Amortized Cost, Net of Allowance for Loan and Lease Losses - Allowance For Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan and lease losses, beginning of period	$ 355,163	$ 243,260	$ 327,852	$ 144,389
Credit loss expense for loans and leases held for investment	64,127	82,599	201,167	204,880
Charge-offs	(74,178)	(23,728)	(191,010)	(48,669)
Recoveries	5,383	1,070	12,486	2,601
Allowance for loan and lease losses, end of period	350,495	303,201	350,495	303,201
Unfunded Loan Commitment
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Reserve for unfunded lending commitments, beginning of period	2,017	2,025	1,878	1,231
Credit loss expense for unfunded lending commitments	352	140	491	934
Reserve for unfunded lending commitments, end of period	2,369	2,165	2,369	2,165
Unfunded Loan Commitment, Commitments To Extend Credit
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Reserve for unfunded lending commitments, beginning of period			138,000
Reserve for unfunded lending commitments, end of period	89,500	144,000	89,500	144,000
Consumer Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan and lease losses, beginning of period	341,161	228,184	312,489	128,812
Credit loss expense for loans and leases held for investment	63,733	81,935	201,291	203,967
Charge-offs	(73,644)	(22,944)	(189,201)	(46,668)
Recoveries	5,038	963	11,709	2,027
Allowance for loan and lease losses, end of period	336,288	288,138	336,288	288,138
Consumer Portfolio Segment \| Unfunded Loan Commitment
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Reserve for unfunded lending commitments, beginning of period	0	136	18	0
Credit loss expense for unfunded lending commitments	0	(78)	(18)	58
Reserve for unfunded lending commitments, end of period	0	58	0	58
Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan and lease losses, beginning of period	14,002	15,076	15,363	15,577
Credit loss expense for loans and leases held for investment	394	664	(124)	913
Charge-offs	(534)	(784)	(1,809)	(2,001)
Recoveries	345	107	777	574
Allowance for loan and lease losses, end of period	14,207	15,063	14,207	15,063
Commercial Portfolio Segment \| Unfunded Loan Commitment
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Reserve for unfunded lending commitments, beginning of period	2,017	1,889	1,860	1,231
Credit loss expense for unfunded lending commitments	352	218	509	876
Reserve for unfunded lending commitments, end of period	$ 2,369	$ 2,107	$ 2,369	$ 2,107

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
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

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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
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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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
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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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
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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- Definition

Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. 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
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482454/460-10-45-1

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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.

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