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	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan and lease losses, beginning of period	$ 348,857	$ 187,985	$ 327,852	$ 144,389
Credit loss expense for loans and leases held for investment	66,190	70,053	137,040	122,281
Charge-offs	(64,269)	(15,852)	(116,832)	(24,941)
Recoveries	4,385	1,074	7,103	1,531
Allowance for loan and lease losses, end of period	355,163	243,260	355,163	243,260
Unfunded Loan Commitment
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Reserve for unfunded lending commitments, beginning of period	1,612	1,512	1,878	1,231
Credit loss expense for unfunded lending commitments	405	513	139	794
Reserve for unfunded lending commitments, end of period	2,017	2,025	2,017	2,025
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	108,900	132,600	108,900	132,600
Consumer Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan and lease losses, beginning of period	333,546	173,857	312,489	128,812
Credit loss expense for loans and leases held for investment	66,874	68,314	137,558	122,032
Charge-offs	(63,345)	(14,707)	(115,557)	(23,724)
Recoveries	4,086	720	6,671	1,064
Allowance for loan and lease losses, end of period	341,161	228,184	341,161	228,184
Consumer Portfolio Segment \| Unfunded Loan Commitment
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Reserve for unfunded lending commitments, beginning of period	67	0	18	0
Credit loss expense for unfunded lending commitments	(67)	136	(18)	136
Reserve for unfunded lending commitments, end of period	0	136	0	136
Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan and lease losses, beginning of period	15,311	14,128	15,363	15,577
Credit loss expense for loans and leases held for investment	(684)	1,739	(518)	249
Charge-offs	(924)	(1,145)	(1,275)	(1,217)
Recoveries	299	354	432	467
Allowance for loan and lease losses, end of period	14,002	15,076	14,002	15,076
Commercial Portfolio Segment \| Unfunded Loan Commitment
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Reserve for unfunded lending commitments, beginning of period	1,545	1,512	1,860	1,231
Credit loss expense for unfunded lending commitments	472	377	157	658
Reserve for unfunded lending commitments, end of period	$ 2,017	$ 1,889	$ 2,017	$ 1,889

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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+ References

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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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- Definition

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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- Definition

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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