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Securities - Continuous Unrealized Loss Position (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Securities
Proceeds from the sale of available for sale investments	$ 7,300,000	$ 26,400,000	$ 20,855,000	$ 44,592,000
Gross gain on sale of available for sale investments	314,000	1,300,000	562,000	1,500,000
Gross loss on sale of available for sale investments	0	$ 0	200,000	$ 202,000,000
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Less than 12 Months	62,188,000		62,188,000		$ 10,529,000
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, 12 Months or Longer	1,007,000		1,007,000		7,443,000
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Total	63,195,000		63,195,000		17,972,000
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Less than 12 Months	(732,000)		(732,000)		(86,000)
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, 12 Months or Longer	(20,000)		(20,000)		(71,000)
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Total	(752,000)		(752,000)		(157,000)
U.S. asset backed securities
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Less than 12 Months	4,158,000		4,158,000		2,884,000
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, 12 Months or Longer					7,443,000
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Total	4,158,000		4,158,000		10,327,000
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Less than 12 Months	(26,000)		(26,000)		(4,000)
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, 12 Months or Longer					(71,000)
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Total	(26,000)		(26,000)		(75,000)
U.S. government agency mortgage-backed securities
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Less than 12 Months	1,614,000		1,614,000
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Total	1,614,000		1,614,000
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Less than 12 Months	(29,000)		(29,000)
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Total	(29,000)		(29,000)
U.S. government agency collateralized mortgage obligations
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Less than 12 Months	7,315,000		7,315,000		2,284,000
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Total	7,315,000		7,315,000		2,284,000
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Less than 12 Months	(142,000)		(142,000)		(17,000)
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Total	(142,000)		(142,000)		(17,000)
State and municipal securities
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Less than 12 Months	34,808,000		34,808,000		4,163,000
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, 12 Months or Longer	568,000		568,000
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Total	35,376,000		35,376,000		4,163,000
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Less than 12 Months	(451,000)		(451,000)		(63,000)
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, 12 Months or Longer	(10,000)		(10,000)
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Total	(461,000)		(461,000)		(63,000)
U.S. Treasuries
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Less than 12 Months	12,049,000		12,049,000
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Total	12,049,000		12,049,000
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Less than 12 Months	(78,000)		(78,000)
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Total	(78,000)		(78,000)
Corporate bonds
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Less than 12 Months	2,244,000		2,244,000		1,198,000
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, 12 Months or Longer	439,000		439,000
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Total	2,683,000		2,683,000		1,198,000
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Less than 12 Months	(6,000)		(6,000)		(2,000)
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, 12 Months or Longer	(10,000)		(10,000)
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Total	$ (16,000)		$ (16,000)		$ (2,000)

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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