Allowance for Credit Losses - Allowance (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Changes in the allowance for loan losses for loans held for investments
Balance, Beginning of Period	$ 91,185	$ 144,499	$ 91,352	$ 149,044
Provision for (Reversal of) Credit Losses	5,336	(28,720)	5,451	(33,829)
Loans Charged Off	(2,024)	(1,553)	(3,361)	(1,921)
Recoveries on Charged Off Loans	801	1,043	1,856	1,975
Balance, End of Period	95,298	115,269	95,298	115,269
Commercial real estate
Changes in the allowance for loan losses for loans held for investments
Balance, Beginning of Period	60,361	104,126	59,354	109,629
Provision for (Reversal of) Credit Losses	3,347	(26,527)	4,322	(32,044)
Loans Charged Off		(186)		(186)
Recoveries on Charged Off Loans	11	220	43	234
Balance, End of Period	63,719	77,633	63,719	77,633
Commercial and industrial
Changes in the allowance for loan losses for loans held for investments
Balance, Beginning of Period	20,130	28,513	21,982	27,703
Provision for (Reversal of) Credit Losses	871	(106)	(679)	450
Loans Charged Off	(1,892)	(1,242)	(3,101)	(1,421)
Recoveries on Charged Off Loans	727	701	1,634	1,134
Balance, End of Period	19,836	27,866	19,836	27,866
Construction and Land Development
Changes in the allowance for loan losses for loans held for investments
Balance, Beginning of Period	5,515	7,249	4,674	6,677
Provision for (Reversal of) Credit Losses	(519)	(2,064)	322	(1,492)
Balance, End of Period	4,996	5,185	4,996	5,185
1 - 4 family residential
Changes in the allowance for loan losses for loans held for investments
Balance, Beginning of Period	4,340	3,388	4,589	3,946
Provision for (Reversal of) Credit Losses	1,212	269	965	(588)
Loans Charged Off	(33)	(51)	(48)	(161)
Recoveries on Charged Off Loans	35	53	48	462
Balance, End of Period	5,554	3,659	5,554	3,659
Consumer
Changes in the allowance for loan losses for loans held for investments
Balance, Beginning of Period	499	944	578	876
Provision for (Reversal of) Credit Losses	114	(347)	45	(276)
Loans Charged Off	(99)	(74)	(212)	(153)
Recoveries on Charged Off Loans	28	69	131	145
Balance, End of Period	542	592	542	592
Broker-dealer
Changes in the allowance for loan losses for loans held for investments
Balance, Beginning of Period	340	279	175	213
Provision for (Reversal of) Credit Losses	311	55	476	121
Balance, End of Period	$ 651	$ 334	$ 651	$ 334

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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- Definition

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

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- Definition

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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