Debt Securities Available for Sale - Continuous Unrealized Loss Position of Available-for-Sale Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	$ 139,261	$ 187,055
Less than 12 months, gross unrealized (losses)	(374)	(965)
12 months or longer, fair value	45,859	72,428
12 months or longer, gross unrealized (losses)	(1,114)	(1,090)
Fair value	185,120	259,483
Gross unrealized (losses)	(1,488)	(2,055)
U.S. government and agency obligations
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value		5,106
Less than 12 months, gross unrealized (losses)		(13)
12 months or longer, fair value		4,988
12 months or longer, gross unrealized (losses)		(3)
Fair value		10,094
Gross unrealized (losses)		(16)
Mortgage-backed securities and collateralized mortgage obligations
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	138,268	178,665
Less than 12 months, gross unrealized (losses)	(367)	(946)
12 months or longer, fair value	36,897	58,208
12 months or longer, gross unrealized (losses)	(76)	(319)
Fair value	175,165	236,873
Gross unrealized (losses)	(443)	(1,265)
Municipal obligations
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value		696
Less than 12 months, gross unrealized (losses)		(1)
12 months or longer, fair value		0
12 months or longer, gross unrealized (losses)		0
Fair value		696
Gross unrealized (losses)		(1)
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	993	2,588
Less than 12 months, gross unrealized (losses)	(7)	(5)
12 months or longer, fair value	4,503	4,627
12 months or longer, gross unrealized (losses)	(498)	(373)
Fair value	5,496	7,215
Gross unrealized (losses)	(505)	(378)
Trust preferred securities
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	0	0
Less than 12 months, gross unrealized (losses)	0	0
12 months or longer, fair value	4,459	4,605
12 months or longer, gross unrealized (losses)	(540)	(395)
Fair value	4,459	4,605
Gross unrealized (losses)	$ (540)	$ (395)

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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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 less 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 less 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 unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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