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Investment Securities - Other Than Temporarily Impaired Debt Securities (Details)	Dec. 31, 2021 USD ($) security	Dec. 31, 2020 USD ($) security
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Number of investment securities in unrealized loss positions | security	217	10
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract]
Held-to-maturity, Less than 12 continuous months, Fair value	$ 201,204,000
Held-to-maturity, Less than 12 continuous months, Unrealized loss	(2,867,000)
Held-to-maturity, Greater than 12 continuous months, Fair value	0
Held-to-maturity, Greater than 12 continuous months, Unrealized loss	0
Held-to-maturity, Total securities in a loss position, Fair value	201,204,000
Held-to-maturity, Total securities in a loss position, Unrealized loss	(2,867,000)	$ 0
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract]
Available-for-sale, Less than 12 continuous months, Fair value	797,781,000	9,918,000
Available-for-sale, Less than 12 continuous months, Unrealized loss	(12,411,000)	(25,000)
Available-for-sale, Greater than 12 continuous months, Fair value	14,173,000	1,790,000
Available-for-sale, Greater than 12 continuous months, Unrealized loss	(615,000)	(55,000)
Available-for-sale, Unrealized loss position, Fair value	811,954,000	11,708,000
Available-for-sale, Total securities in a loss position, Unrealized loss	(13,026,000)	(80,000)
Available-for-sale and Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Total temporarily impaired securities, Less than 12 continuous months, Fair value	998,985,000	9,918,000
Total temporarily impaired securities, Less than 12 continuous months, Unrealized loss	(15,278,000)	(25,000)
Total temporarily impaired securities, Greater than 12 continuous months, Fair value	14,173,000	1,790,000
Total temporarily impaired securities, Greater than 12 continuous months, Unrealized loss	(615,000)	(55,000)
Total temporarily impaired securities, Total securities in a loss position, Fair value	1,013,158,000	11,708,000
Total temporarily impaired securities, Total securities in a loss position, Unrealized loss	$ (15,893,000)	(80,000)
Number of securities in continuous loss position for more than 12 months | security	9
Number of securities in continuous loss position for less than 12 months | security	208
Available-for-sale securities in unrealized loss position, allowance for credit loss	$ 0
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	76,619,000
Held-to-maturity, Less than 12 continuous months, Unrealized loss	(712,000)
Held-to-maturity, Greater than 12 continuous months, Fair value	0
Held-to-maturity, Greater than 12 continuous months, Unrealized loss	0
Held-to-maturity, Total securities in a loss position, Fair value	76,619,000
Held-to-maturity, Total securities in a loss position, Unrealized loss	(712,000)	0
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract]
Available-for-sale, Less than 12 continuous months, Fair value	263,474,000
Available-for-sale, Less than 12 continuous months, Unrealized loss	(2,784,000)
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	263,474,000
Available-for-sale, Total securities in a loss position, Unrealized loss	(2,784,000)
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
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract]
Available-for-sale, Less than 12 continuous months, Fair value	7,478,000	0
Available-for-sale, Less than 12 continuous months, Unrealized loss	(112,000)	0
Available-for-sale, Greater than 12 continuous months, Fair value	1,209,000	1,790,000
Available-for-sale, Greater than 12 continuous months, Unrealized loss	(43,000)	(55,000)
Available-for-sale, Unrealized loss position, Fair value	8,687,000	1,790,000
Available-for-sale, Total securities in a loss position, Unrealized loss	(155,000)	(55,000)
CMOs issued by FHLMC
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract]
Held-to-maturity, Less than 12 continuous months, Fair value	54,811,000
Held-to-maturity, Less than 12 continuous months, Unrealized loss	(1,045,000)
Held-to-maturity, Greater than 12 continuous months, Fair value	0
Held-to-maturity, Greater than 12 continuous months, Unrealized loss	0
Held-to-maturity, Total securities in a loss position, Fair value	54,811,000
Held-to-maturity, Total securities in a loss position, Unrealized loss	(1,045,000)	0
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract]
Available-for-sale, Less than 12 continuous months, Fair value	226,175,000	5,975,000
Available-for-sale, Less than 12 continuous months, Unrealized loss	(4,677,000)	(1,000)
Available-for-sale, Greater than 12 continuous months, Fair value	4,415,000	0
Available-for-sale, Greater than 12 continuous months, Unrealized loss	(152,000)	0
Available-for-sale, Unrealized loss position, Fair value	230,590,000	5,975,000
Available-for-sale, Total securities in a loss position, Unrealized loss	(4,829,000)	(1,000)
CMOs issued by GNMA
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract]
Available-for-sale, Less than 12 continuous months, Fair value	44,790,000
Available-for-sale, Less than 12 continuous months, Unrealized loss	(553,000)
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	44,790,000
Available-for-sale, Total securities in a loss position, Unrealized loss	(553,000)
CMOs issued by FNMA
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract]
Held-to-maturity, Total securities in a loss position, Unrealized loss	0	0
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract]
Available-for-sale, Less than 12 continuous months, Fair value	37,348,000
Available-for-sale, Less than 12 continuous months, Unrealized loss	(611,000)
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	37,348,000
Available-for-sale, Total securities in a loss position, Unrealized loss	(611,000)
Debentures of government-sponsored agencies
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract]
Held-to-maturity, Less than 12 continuous months, Fair value	50,571,000
Held-to-maturity, Less than 12 continuous months, Unrealized loss	(901,000)
Held-to-maturity, Greater than 12 continuous months, Fair value	0
Held-to-maturity, Greater than 12 continuous months, Unrealized loss	0
Held-to-maturity, Total securities in a loss position, Fair value	50,571,000
Held-to-maturity, Total securities in a loss position, Unrealized loss	(901,000)
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract]
Available-for-sale, Less than 12 continuous months, Fair value	148,979,000	3,943,000
Available-for-sale, Less than 12 continuous months, Unrealized loss	(2,527,000)	(24,000)
Available-for-sale, Greater than 12 continuous months, Fair value	8,549,000	0
Available-for-sale, Greater than 12 continuous months, Unrealized loss	(420,000)	0
Available-for-sale, Unrealized loss position, Fair value	157,528,000	3,943,000
Available-for-sale, Total securities in a loss position, Unrealized loss	(2,947,000)	(24,000)
U.S. Treasury securities
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract]
Available-for-sale, Less than 12 continuous months, Fair value	11,629,000
Available-for-sale, Less than 12 continuous months, Unrealized loss	(256,000)
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	11,629,000
Available-for-sale, Total securities in a loss position, Unrealized loss	(256,000)
Obligations of state and political subdivisions
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract]
Held-to-maturity, Less than 12 continuous months, Fair value	19,203,000
Held-to-maturity, Less than 12 continuous months, Unrealized loss	(209,000)
Held-to-maturity, Greater than 12 continuous months, Fair value	0
Held-to-maturity, Greater than 12 continuous months, Unrealized loss	0
Held-to-maturity, Total securities in a loss position, Fair value	19,203,000
Held-to-maturity, Total securities in a loss position, Unrealized loss	(209,000)	$ 0
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract]
Available-for-sale, Less than 12 continuous months, Fair value	17,552,000
Available-for-sale, Less than 12 continuous months, Unrealized loss	(381,000)
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	17,552,000
Available-for-sale, Total securities in a loss position, Unrealized loss	(381,000)
Corporate bonds
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract]
Available-for-sale, Less than 12 continuous months, Fair value	38,495,000
Available-for-sale, Less than 12 continuous months, Unrealized loss	(506,000)
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	38,495,000
Available-for-sale, Total securities in a loss position, Unrealized loss	(506,000)
Asset-backed securities
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract]
Available-for-sale, Less than 12 continuous months, Fair value	1,861,000
Available-for-sale, Less than 12 continuous months, Unrealized loss	(4,000)
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	1,861,000
Available-for-sale, Total securities in a loss position, Unrealized loss	$ (4,000)

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-Publisher FASB
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- Definition

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

+ References

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- Definition

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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