Securities - Debt Securities, Held-to-maturity (Details) - USD ($)	Mar. 31, 2022	Dec. 31, 2021
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	$ 395,434,000	$ 0
Unrealized Gains	17,000
Unrealized Losses	(3,328,000)
Allowance for Credit Losses	0
Fair Value	392,123,000	$ 0
Government-sponsored residential mortgage-backed securities
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	192,231,000
Unrealized Gains	0
Unrealized Losses	(3,318,000)
Allowance for Credit Losses	0
Fair Value	188,913,000
Government-sponsored commercial mortgage-backed securities
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	203,203,000
Unrealized Gains	17,000
Unrealized Losses	(10,000)
Allowance for Credit Losses	0
Fair Value	$ 203,210,000

Amount, excluding accrued interest, of allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity).

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

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Amount excluding accrued interest, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27232-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=SL120269820-111563

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