Allowance for Credit Losses - Allowance (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Changes in the allowance for loan losses for loans held for investments
Balance, Beginning of Period	$ 95,298	$ 115,269	$ 91,352	$ 149,044
Provision for (Reversal of) Credit Losses	(780)	(5,819)	4,671	(39,648)
Loans Charged Off	(3,259)	(601)	(6,620)	(2,522)
Recoveries on Charged Off Loans	524	663	2,380	2,638
Balance, End of Period	91,783	109,512	91,783	109,512
Commercial real estate
Changes in the allowance for loan losses for loans held for investments
Balance, Beginning of Period	63,719	77,633	59,354	109,629
Provision for (Reversal of) Credit Losses	(560)	(8,993)	3,762	(41,037)
Loans Charged Off		(124)		(310)
Recoveries on Charged Off Loans	41	19	84	253
Balance, End of Period	63,200	68,535	63,200	68,535
Commercial and industrial
Changes in the allowance for loan losses for loans held for investments
Balance, Beginning of Period	19,836	27,866	21,982	27,703
Provision for (Reversal of) Credit Losses	(1,002)	2,398	(1,681)	2,848
Loans Charged Off	(3,096)	(317)	(6,197)	(1,738)
Recoveries on Charged Off Loans	370	598	2,004	1,732
Balance, End of Period	16,108	30,545	16,108	30,545
Construction and Land Development
Changes in the allowance for loan losses for loans held for investments
Balance, Beginning of Period	4,996	5,185	4,674	6,677
Provision for (Reversal of) Credit Losses	(228)	(85)	94	(1,577)
Balance, End of Period	4,768	5,100	4,768	5,100
1 - 4 family residential
Changes in the allowance for loan losses for loans held for investments
Balance, Beginning of Period	5,554	3,659	4,589	3,946
Provision for (Reversal of) Credit Losses	1,049	946	2,014	358
Loans Charged Off	(14)	(87)	(62)	(248)
Recoveries on Charged Off Loans	23	20	71	482
Balance, End of Period	6,612	4,538	6,612	4,538
Consumer
Changes in the allowance for loan losses for loans held for investments
Balance, Beginning of Period	542	592	578	876
Provision for (Reversal of) Credit Losses	91	(41)	136	(317)
Loans Charged Off	(149)	(73)	(361)	(226)
Recoveries on Charged Off Loans	90	26	221	171
Balance, End of Period	574	504	574	504
Broker-dealer
Changes in the allowance for loan losses for loans held for investments
Balance, Beginning of Period	651	334	175	213
Provision for (Reversal of) Credit Losses	(130)	(44)	346	77
Balance, End of Period	$ 521	$ 290	$ 521	$ 290

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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

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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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Amount of credit loss expense (reversal of expense) for financing receivable.

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