Loans - Major Categories of Loans Held for Investment and the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Major categories of loans held for investment and the allowance for loan losses
Total loans	$ 2,012,814	$ 2,506,743
Less: allowance for loan losses	(56,548)	(72,387)	$ (21,730)	$ (21,850)
Loans, net	1,956,266	2,434,356
Carrying value of loans pledged as collateral on FHLB borrowings	557,410	630,197
Residential real estate
Major categories of loans held for investment and the allowance for loan losses
Total loans	1,704,231	2,033,526
Less: allowance for loan losses	(32,202)	(32,366)	(12,336)	(13,826)
Loans, net	237,049	562,139
Commercial real estate
Major categories of loans held for investment and the allowance for loan losses
Total loans	201,240	259,958
Less: allowance for loan losses	(12,608)	(21,942)	(5,243)	(2,573)
Loans, net	53,628
Construction
Major categories of loans held for investment and the allowance for loan losses
Total loans	106,759	206,581
Less: allowance for loan losses	(11,730)	(17,988)	(3,822)	(3,273)
Commercial lines of credit
Major categories of loans held for investment and the allowance for loan losses
Total loans	363	6,671
Less: allowance for loan losses	(8)	(91)	(328)	(1,058)
Other consumer
Major categories of loans held for investment and the allowance for loan losses
Total loans	$ 221	$ 7
Less: allowance for loan losses			$ (1)	$ (1)

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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