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Investment Securities - Held-to-Maturity Securities Amortized Cost and Fair Value (Details) - USD ($)		Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost		$ 342,222,000	$ 109,036,000
Allowance for Credit Losses	[1]	0	0
Net Carrying Amount		342,222,000	109,036,000
Gross Unrealized Gains		3,400,000	6,149,000
Gross Unrealized (Losses)		(2,867,000)	0
Fair Value		342,755,000	115,185,000
Other assets
Debt Securities, Held-to-maturity [Abstract]
Accrued interest		1,100,000	366,000
MBS pass-through securities issued by FHLMC and FNMA
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost		126,990,000	65,579,000
Allowance for Credit Losses		0	0
Net Carrying Amount		126,990,000	65,579,000
Gross Unrealized Gains		2,110,000	3,924,000
Gross Unrealized (Losses)		(712,000)	0
Fair Value		128,388,000	69,503,000
CMOs issued by FHLMC
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost		106,851,000	27,201,000
Allowance for Credit Losses		0	0
Net Carrying Amount		106,851,000	27,201,000
Gross Unrealized Gains		668,000	1,441,000
Gross Unrealized (Losses)		(1,045,000)	0
Fair Value		106,474,000	28,642,000
CMOs issued by FNMA
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost		4,866,000	8,042,000
Allowance for Credit Losses		0	0
Net Carrying Amount		4,866,000	8,042,000
Gross Unrealized Gains		128,000	363,000
Gross Unrealized (Losses)		0	0
Fair Value		4,994,000	8,405,000
SBA-backed securities
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost		4,840,000	6,547,000
Allowance for Credit Losses		0	0
Net Carrying Amount		4,840,000	6,547,000
Gross Unrealized Gains		198,000	400,000
Gross Unrealized (Losses)		0	0
Fair Value		5,038,000	6,947,000
Debentures of government sponsored agencies
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost		51,472,000
Allowance for Credit Losses
Net Carrying Amount		51,472,000
Gross Unrealized Gains		0
Gross Unrealized (Losses)		(901,000)
Fair Value		50,571,000
Obligations of state and political subdivisions
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost		47,203,000	1,667,000
Allowance for Credit Losses		0	0
Net Carrying Amount		47,203,000	1,667,000
Gross Unrealized Gains		296,000	21,000
Gross Unrealized (Losses)		(209,000)	0
Fair Value		$ 47,290,000	$ 1,688,000
[1] Refer to Note 1, Summary of Accounting Policies, for information on the adoption of ASU 2016-13 in 2020.

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

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