Disclosures about Fair Value of Assets and Liabilities - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Disclosures about Fair Value of Assets and Liabilities
Mortgage loans in process of securitization	$ 137,448	$ 569,239
Available for sale securities	322,069	310,629
Loans held for sale	68,785	48,583
Servicing rights	144,984	110,348
Recurring
Disclosures about Fair Value of Assets and Liabilities
Mortgage loans in process of securitization	137,448	569,239
Loans held for sale	68,785	48,583
Servicing rights	144,984	110,348
Recurring \| Interest rate lock commitments
Disclosures about Fair Value of Assets and Liabilities
Derivative assets	24	264
Derivative liabilities	438	41
Recurring \| Forward contracts
Disclosures about Fair Value of Assets and Liabilities
Derivative assets	1,046	86
Derivative liabilities	2	118
Recurring \| Interest rate swaps
Disclosures about Fair Value of Assets and Liabilities
Derivative assets	3,405
Recurring \| Interest rate swaps (back-to-back)
Disclosures about Fair Value of Assets and Liabilities
Derivative assets	3,413	1,131
Derivative liabilities	3,413	1,131
Level 2 \| Recurring
Disclosures about Fair Value of Assets and Liabilities
Mortgage loans in process of securitization	137,448	569,239
Loans held for sale	68,785	48,583
Level 2 \| Recurring \| Forward contracts
Disclosures about Fair Value of Assets and Liabilities
Derivative assets	1,046	86
Derivative liabilities	2	118
Level 2 \| Recurring \| Interest rate swaps
Disclosures about Fair Value of Assets and Liabilities
Derivative assets	3,405
Level 2 \| Recurring \| Interest rate swaps (back-to-back)
Disclosures about Fair Value of Assets and Liabilities
Derivative assets	3,413	1,131
Derivative liabilities	3,413	1,131
Level 3 \| Interest rate lock commitments
Disclosures about Fair Value of Assets and Liabilities
Derivative assets	24	264
Derivative liabilities	438	41
Level 3 \| Recurring
Disclosures about Fair Value of Assets and Liabilities
Servicing rights	144,984	110,348
Level 3 \| Recurring \| Interest rate lock commitments
Disclosures about Fair Value of Assets and Liabilities
Derivative assets	24	264
Derivative liabilities	438	41
Treasury notes
Disclosures about Fair Value of Assets and Liabilities
Available for sale securities	36,312	8,209
Treasury notes \| Recurring
Disclosures about Fair Value of Assets and Liabilities
Available for sale securities	36,312	8,209
Treasury notes \| Level 1 \| Recurring
Disclosures about Fair Value of Assets and Liabilities
Available for sale securities	36,312	8,209
Federal agencies
Disclosures about Fair Value of Assets and Liabilities
Available for sale securities	270,353	263,295
Federal agencies \| Recurring
Disclosures about Fair Value of Assets and Liabilities
Available for sale securities	270,353	263,295
Federal agencies \| Level 2 \| Recurring
Disclosures about Fair Value of Assets and Liabilities
Available for sale securities	270,353	263,295
Municipals \| Recurring
Disclosures about Fair Value of Assets and Liabilities
Available for sale securities		4,300
Municipals \| Level 2 \| Recurring
Disclosures about Fair Value of Assets and Liabilities
Available for sale securities		4,300
Mortgage-backed - Government-sponsored entity (GSE)
Disclosures about Fair Value of Assets and Liabilities
Available for sale securities	15,404	18,360
Mortgage-backed - Government-sponsored entity (GSE) \| Recurring
Disclosures about Fair Value of Assets and Liabilities
Available for sale securities	15,404	18,360
Mortgage-backed - Government-sponsored entity (GSE) \| Level 2 \| Recurring
Disclosures about Fair Value of Assets and Liabilities
Available for sale securities	$ 15,404	18,360
Mortgage-backed - Non-GSE multi-family
Disclosures about Fair Value of Assets and Liabilities
Available for sale securities		16,465
Mortgage-backed - Non-GSE multi-family \| Recurring
Disclosures about Fair Value of Assets and Liabilities
Available for sale securities		16,465
Mortgage-backed - Non-GSE multi-family \| Level 2 \| Recurring
Disclosures about Fair Value of Assets and Liabilities
Available for sale securities		$ 16,465

Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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-Publisher FASB
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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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