Investment Securities - Other Than Temporarily Impaired Debt Securities (Details) $ in Thousands	Dec. 31, 2020 USD ($) security	Dec. 31, 2019 USD ($) security
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Number of investment securities in unrealized loss positions \| security	10	40
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract]
Held-to-maturity, Less than 12 continuous months, Fair value		$ 14,203
Held-to-maturity, Less than 12 continuous months, Unrealized loss		(60)
Held-to-maturity, Greater than 12 continuous months, Fair value		7,798
Held-to-maturity, Greater than 12 continuous months, Unrealized loss		(89)
Held-to-maturity, Total securities in a loss position, Fair value		22,001
Held-to-maturity, Total securities in a loss position, Unrealized loss	$ 0	(149)
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] (Deprecated 2019-01-31)
Available-for-sale, Less than 12 continuous months, Fair value	9,918	81,958
Available-for-sale, Less than 12 continuous months, Unrealized loss	(25)	(328)
Available-for-sale, Greater than 12 continuous months, Fair value	1,790	10,552
Available-for-sale, Greater than 12 continuous months, Unrealized loss	(55)	(83)
Available-for-sale, Unrealized loss position, Fair value	11,708	92,510
Available-for-sale, Total securities in a loss position, Unrealized loss	$ (80)	(411)
Available-for-sale and Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract] [Abstract]
Total temporarily impaired securities, Less than 12 continuous months, Fair value		96,161
Total temporarily impaired securities, Less than 12 continuous months, Unrealized loss		(388)
Total temporarily impaired securities, Greater than 12 continuous months, Fair value		18,350
Total temporarily impaired securities, Greater than 12 continuous months, Unrealized loss		(172)
Total temporarily impaired securities, Total securities in a loss position, Fair value		114,511
Total temporarily impaired securities, Total securities in a loss position, Unrealized loss		(560)
Number of securities in continuous loss position for more than 12 months \| security	5
Number of securities in continuous loss position for less than 12 months \| security	5
MBS pass-through securities issued by FHLMC and FNMA
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract]
Held-to-maturity, Less than 12 continuous months, Fair value		14,203
Held-to-maturity, Less than 12 continuous months, Unrealized loss		(60)
Held-to-maturity, Greater than 12 continuous months, Fair value		6,073
Held-to-maturity, Greater than 12 continuous months, Unrealized loss		(84)
Held-to-maturity, Total securities in a loss position, Fair value		20,276
Held-to-maturity, Total securities in a loss position, Unrealized loss	$ 0	(144)
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] (Deprecated 2019-01-31)
Available-for-sale, Less than 12 continuous months, Fair value		4,367
Available-for-sale, Less than 12 continuous months, Unrealized loss		(34)
Available-for-sale, Greater than 12 continuous months, Fair value		4,464
Available-for-sale, Greater than 12 continuous months, Unrealized loss		(14)
Available-for-sale, Unrealized loss position, Fair value		8,831
Available-for-sale, Total securities in a loss position, Unrealized loss		(48)
SBA-backed securities
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract]
Held-to-maturity, Total securities in a loss position, Unrealized loss	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] (Deprecated 2019-01-31)
Available-for-sale, Less than 12 continuous months, Fair value	0	9,227
Available-for-sale, Less than 12 continuous months, Unrealized loss	0	(14)
Available-for-sale, Greater than 12 continuous months, Fair value	1,790	2,448
Available-for-sale, Greater than 12 continuous months, Unrealized loss	(55)	(62)
Available-for-sale, Unrealized loss position, Fair value	1,790	11,675
Available-for-sale, Total securities in a loss position, Unrealized loss	(55)	(76)
CMOs issued by FHLMC
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract]
Held-to-maturity, Less than 12 continuous months, Fair value		0
Held-to-maturity, Less than 12 continuous months, Unrealized loss		0
Held-to-maturity, Greater than 12 continuous months, Fair value		1,725
Held-to-maturity, Greater than 12 continuous months, Unrealized loss		(5)
Held-to-maturity, Total securities in a loss position, Fair value		1,725
Held-to-maturity, Total securities in a loss position, Unrealized loss	0	(5)
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] (Deprecated 2019-01-31)
Available-for-sale, Less than 12 continuous months, Fair value	5,975	14,918
Available-for-sale, Less than 12 continuous months, Unrealized loss	(1)	(58)
Available-for-sale, Greater than 12 continuous months, Fair value	0	2,981
Available-for-sale, Greater than 12 continuous months, Unrealized loss	0	(6)
Available-for-sale, Unrealized loss position, Fair value	5,975	17,899
Available-for-sale, Total securities in a loss position, Unrealized loss	(1)	(64)
CMOs issued by GNMA
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract]
Held-to-maturity, Total securities in a loss position, Unrealized loss		0
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] (Deprecated 2019-01-31)
Available-for-sale, Less than 12 continuous months, Fair value		7,139
Available-for-sale, Less than 12 continuous months, Unrealized loss		(6)
Available-for-sale, Greater than 12 continuous months, Fair value		0
Available-for-sale, Greater than 12 continuous months, Unrealized loss		0
Available-for-sale, Unrealized loss position, Fair value		7,139
Available-for-sale, Total securities in a loss position, Unrealized loss		(6)
Debentures of government-sponsored agencies
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] (Deprecated 2019-01-31)
Available-for-sale, Less than 12 continuous months, Fair value	3,943	25,228
Available-for-sale, Less than 12 continuous months, Unrealized loss	(24)	(70)
Available-for-sale, Greater than 12 continuous months, Fair value	0	0
Available-for-sale, Greater than 12 continuous months, Unrealized loss	0	0
Available-for-sale, Unrealized loss position, Fair value	3,943	25,228
Available-for-sale, Total securities in a loss position, Unrealized loss	(24)	(70)
Obligations of state and political subdivisions
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract]
Held-to-maturity, Total securities in a loss position, Unrealized loss		0
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] (Deprecated 2019-01-31)
Available-for-sale, Less than 12 continuous months, Fair value		20,579
Available-for-sale, Less than 12 continuous months, Unrealized loss		(145)
Available-for-sale, Greater than 12 continuous months, Fair value		659
Available-for-sale, Greater than 12 continuous months, Unrealized loss		(1)
Available-for-sale, Unrealized loss position, Fair value		21,238
Available-for-sale, Total securities in a loss position, Unrealized loss		(146)
Corporate bonds
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] (Deprecated 2019-01-31)
Available-for-sale, Less than 12 continuous months, Fair value		500
Available-for-sale, Less than 12 continuous months, Unrealized loss		(1)
Available-for-sale, Greater than 12 continuous months, Fair value		0
Available-for-sale, Greater than 12 continuous months, Unrealized loss		0
Available-for-sale, Unrealized loss position, Fair value		500
Available-for-sale, Total securities in a loss position, Unrealized loss		$ (1)

Available-for-sale Securities and Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value, Total

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Available-for-sale Securities and Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value

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Available-for-sale Securities and Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value

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Available-for-sale Securities and Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss

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Available-for-sale Securities and Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss

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Available-for-sale and Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract] [Abstract]

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Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract]

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Marketable Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions

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Marketable Securities In Unrealized Loss Positions, Qualitative Disclosure, Number Of Positions, Longer Than 12 Months

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Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]

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

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