Securities, HTM Securities in Continuous Unrealized Loss Position (Details) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2021 USD ($) Position	Dec. 31, 2020 USD ($) Position
Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months	$ 151,842	$ 103,147
12 months or longer	0	0
Total	151,842	103,147
Unrealized Loss Position, Unrealized Losses [Abstract]
Less than 12 months	(4,219)	(1,675)
12 months or longer	0	0
Total	$ (4,219)	$ (1,675)
Unrealized Loss Position, Number of Positions [Abstract]
Less than 12 months \| Position	43	9
12 months or longer \| Position	0	0
Total \| Position	43	9
HTM debt securities	$ 622,351	$ 616,560
Accrued interest reversed against interest income	0	0
Collateral-dependent HTM debt securities	0	0
AIR on HTM debt securities	2,600	2,700
Past Due [Member]
Unrealized Loss Position, Number of Positions [Abstract]
HTM debt securities	0	0
Federal Agency [Member]
Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months	96,707	98,342
12 months or longer	0	0
Total	96,707	98,342
Unrealized Loss Position, Unrealized Losses [Abstract]
Less than 12 months	(3,293)	(1,658)
12 months or longer	0	0
Total	$ (3,293)	$ (1,658)
Unrealized Loss Position, Number of Positions [Abstract]
Less than 12 months \| Position	4	4
12 months or longer \| Position	0	0
Total \| Position	4	4
HTM debt securities	$ 100,000	$ 100,000
Mortgage-Backed [Member]
Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months	7,710
12 months or longer	0
Total	7,710
Unrealized Loss Position, Unrealized Losses [Abstract]
Less than 12 months	(38)
12 months or longer	0
Total	$ (38)
Unrealized Loss Position, Number of Positions [Abstract]
Less than 12 months \| Position	1
12 months or longer \| Position	0
Total \| Position	1
State & Municipal [Member]
Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months	$ 47,425	4,805
12 months or longer	0	0
Total	47,425	4,805
Unrealized Loss Position, Unrealized Losses [Abstract]
Less than 12 months	(888)	(17)
12 months or longer	0	0
Total	$ (888)	$ (17)
Unrealized Loss Position, Number of Positions [Abstract]
Less than 12 months \| Position	38	5
12 months or longer \| Position	0	0
Total \| Position	38	5
HTM debt securities	$ 275,002	$ 214,863
US Government Agencies Debt Securities and US Government-sponsored Enterprises Debt Securities [Member]
Unrealized Loss Position, Number of Positions [Abstract]
Held-to-maturity debt securities, percentage	56.00%	65.00%

Amount of reversed for accrued interest receivable on the HTM debt securities during the period.

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Amount of held-to-maturity securities that are collateral dependent.

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Number of investment positions in held-to-maturity investments in a continuous unrealized loss position for greater than or equal to a year for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

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Number of investment positions in held-to-maturity investments in a continuous unrealized loss position for less than one year or normal operating cycle, if longer, for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

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

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

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

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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in continuous loss position for 12 months or longer.

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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in unrealized loss position.

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

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Fair value of investment in debt security measured at amortized cost (held-to-maturity), in continuous unrealized loss position for 12 months or longer.

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