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Investment Securities - Available-for-Sale Securities Amortized Cost and Fair Value (Details) - USD ($)	Jun. 30, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	$ 504,934,000	$ 373,038,000
Available-for-sale, gross unrealized gains	15,516,000	19,393,000
Available-for-sale, gross unrealized losses	(2,487,000)	(80,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	517,963,000	392,351,000
Accrued interest	2,400,000	1,900,000
MBS pass-through securities issued by FHLMC and FNMA
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	57,653,000	50,686,000
Available-for-sale, gross unrealized gains	1,867,000	2,530,000
Available-for-sale, gross unrealized losses	0	0
Allowance for Credit Losses	0	0
Available-for-sale securities	59,520,000	53,216,000
CMOs issued by FHLMC
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	160,949,000	143,267,000
Available-for-sale, gross unrealized gains	5,573,000	7,925,000
Available-for-sale, gross unrealized losses	(436,000)	(1,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	166,086,000	151,191,000
CMOs issued by FNMA
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	36,636,000	16,450,000
Available-for-sale, gross unrealized gains	428,000	580,000
Available-for-sale, gross unrealized losses	0	0
Allowance for Credit Losses	0	0
Available-for-sale securities	37,064,000	17,030,000
CMOs issued by GNMA
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	21,855,000	6,863,000
Available-for-sale, gross unrealized gains	258,000	351,000
Available-for-sale, gross unrealized losses	0	0
Allowance for Credit Losses	0	0
Available-for-sale securities	22,113,000	7,214,000
SBA-backed securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	27,938,000	30,941,000
Available-for-sale, gross unrealized gains	1,568,000	1,976,000
Available-for-sale, gross unrealized losses	(46,000)	(55,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	29,460,000	32,862,000
Debentures of government- sponsored agencies
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	76,321,000	19,944,000
Available-for-sale, gross unrealized gains	128,000	266,000
Available-for-sale, gross unrealized losses	(1,738,000)	(24,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	74,711,000	20,186,000
Obligations of state and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	117,595,000	104,887,000
Available-for-sale, gross unrealized gains	5,694,000	5,765,000
Available-for-sale, gross unrealized losses	(65,000)	0
Allowance for Credit Losses	0	0
Available-for-sale securities	123,224,000	$ 110,652,000
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	5,987,000
Available-for-sale, gross unrealized gains	0
Available-for-sale, gross unrealized losses	(202,000)
Allowance for Credit Losses	0
Available-for-sale securities	$ 5,785,000

X

- Definition

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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

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