Loans and Allowance for Credit Losses - Financing Receivable, Allowance for Credit Loss (Details) - USD ($) $ in Thousands		3 Months Ended
Jan. 01, 2021	Mar. 31, 2022	Mar. 31, 2021
Balance at beginning of period		$ 60,754
Provision for Loan and Lease Losses		0	$ 300
Balance at end of period		60,797
Allowance for credit losses
Balance at beginning of period	$ 67,338	60,754	67,338
Provision (credit) charged to expense			300
Losses charged off		(437)	(655)
Recoveries		480	719
Balance at end of period	55,743	60,797	67,702
CECL adoption \| Allowance for credit losses
Provision for Loan and Lease Losses	11,595
Loans Receivable \| Allowance for unfunded commitment
Balance at beginning of period	8,690	9,629	8,690
Provision (credit) charged to expense		(193)	(673)
Balance at end of period		9,436	8,017
Loans Receivable \| CECL adoption \| Allowance for unfunded commitment
Provision for Loan and Lease Losses	8,690
Commercial Real Estate \| Allowance for unfunded commitment
Balance at beginning of period	354	367	354
Provision (credit) charged to expense		56	103
Balance at end of period		423	457
Commercial Real Estate \| Allowance for credit losses
Balance at beginning of period	31,176	28,604	31,176
Provision (credit) charged to expense			300
Recoveries			24
Balance at end of period	33,707	28,604	31,500
Commercial Real Estate \| CECL adoption \| Allowance for unfunded commitment
Provision for Loan and Lease Losses	354
Commercial Real Estate \| CECL adoption \| Allowance for credit losses
Provision for Loan and Lease Losses	(2,531)
Commercial construction \| Allowance for unfunded commitment
Balance at beginning of period	910	908	910
Provision (credit) charged to expense		161	(400)
Balance at end of period		1,069	510
Commercial construction \| Allowance for credit losses
Balance at beginning of period	2,356	2,797	2,356
Recoveries			10
Balance at end of period	3,521	2,797	2,366
Commercial construction \| CECL adoption \| Allowance for unfunded commitment
Provision for Loan and Lease Losses	910
Commercial construction \| CECL adoption \| Allowance for credit losses
Provision for Loan and Lease Losses	(1,165)
One- to four-family residential construction \| Allowance for unfunded commitment
Balance at beginning of period	917	687	917
Provision (credit) charged to expense		512	40
Balance at end of period		1,199	957
One- to four-family residential construction \| Allowance for credit losses
Balance at beginning of period	9,069	9,364	9,069
Losses charged off		(36)	(6)
Recoveries		54	38
Balance at end of period	4,536	9,382	9,101
One- to four-family residential construction \| CECL adoption \| Allowance for unfunded commitment
Provision for Loan and Lease Losses	917
One- to four-family residential construction \| CECL adoption \| Allowance for credit losses
Provision for Loan and Lease Losses	4,533
Other residential \| Allowance for unfunded commitment
Balance at beginning of period	5,227	5,703	5,227
Provision (credit) charged to expense		(1,003)	(412)
Balance at end of period		4,700	4,815
Other residential \| Allowance for credit losses
Balance at beginning of period	15,207	10,502	15,207
Recoveries			92
Balance at end of period	9,375	10,502	15,299
Other residential \| CECL adoption \| Allowance for unfunded commitment
Provision for Loan and Lease Losses	5,227
Other residential \| CECL adoption \| Allowance for credit losses
Provision for Loan and Lease Losses	5,832
Commercial business \| Allowance for unfunded commitment
Balance at beginning of period	935	1,582	935
Provision (credit) charged to expense		36	21
Balance at end of period		1,618	956
Commercial business \| Allowance for credit losses
Balance at beginning of period	3,889	4,142	3,889
Recoveries		20	47
Balance at end of period	2,390	4,162	3,936
Commercial business \| CECL adoption \| Allowance for unfunded commitment
Provision for Loan and Lease Losses	935
Commercial business \| CECL adoption \| Allowance for credit losses
Provision for Loan and Lease Losses	1,499
Consumer \| Allowance for unfunded commitment
Balance at beginning of period	347	382	347
Provision (credit) charged to expense		45	(25)
Balance at end of period		427	322
Consumer \| Allowance for credit losses
Balance at beginning of period	5,641	5,345	5,641
Losses charged off		(401)	(649)
Recoveries		406	508
Balance at end of period	2,214	$ 5,350	$ 5,500
Consumer \| CECL adoption \| Allowance for unfunded commitment
Provision for Loan and Lease Losses	347
Consumer \| CECL adoption \| Allowance for credit losses
Provision for Loan and Lease Losses	$ 3,427

Amount of increase in allowance for credit loss on accounts 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 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 of expense related to estimated loss from loan and lease transactions.

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

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