Securities - Debt Securities, Held-to-maturity (Details) - USD ($)	Sep. 30, 2022	Dec. 31, 2021
Schedule of Held-to-Maturity Securities [Line Items]
Amortized Cost	$ 481,963,000	$ 0
Unrealized Gains	0
Unrealized Losses	(50,486,000)
Allowance for Credit Losses	0
Debt Securities, Held-to-Maturity, Fair Value	431,477,000	$ 0
Government-sponsored residential mortgage-backed securities
Schedule of Held-to-Maturity Securities [Line Items]
Amortized Cost	281,253,000
Unrealized Gains	0
Unrealized Losses	(30,972,000)
Allowance for Credit Losses	0
Debt Securities, Held-to-Maturity, Fair Value	250,281,000
Government-sponsored commercial mortgage-backed securities
Schedule of Held-to-Maturity Securities [Line Items]
Amortized Cost	200,710,000
Unrealized Gains	0
Unrealized Losses	(19,514,000)
Allowance for Credit Losses	0
Debt Securities, Held-to-Maturity, Fair Value	$ 181,196,000

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 https://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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of accumulated unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity).

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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