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Securities - Contractual Maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Amortized Cost
Due in one year or less	$ 0
Due after one year through five years	0
Due after five years through ten years	22,934
Due after ten years	0
Held to maturity, amortized cost	22,934
Fair Value
Due in one year or less	0
Due after one year through five years	0
Due after five years through ten years	25,117
Due after ten years	0
Held to maturity, fair value	25,117	$ 41,205
Amortized Cost
Due in one year or less	5,618
Due after one year through five years	117,609
Due after five years through ten years	153,260
Due after ten years	296,949
Available for sale, amortized cost	1,497,458	971,595
Fair Value
Due in one year or less	5,623
Due after one year through five years	120,398
Due after five years through ten years	155,903
Due after ten years	304,286
Available for sale, fair value	1,504,728	1,004,674
Commercial mortgage-backed securities
Amortized Cost
Without single maturity date	0
Fair Value
Without single maturity date	0
Amortized Cost
Without single maturity date	65,691
Available for sale, amortized cost	65,691	10,814
Fair Value
Without single maturity date	64,243
Available for sale, fair value	64,243	11,080
Residential mortgage-backed securities
Amortized Cost
Without single maturity date	0
Fair Value
Without single maturity date	0
Amortized Cost
Without single maturity date	559,655
Available for sale, amortized cost	559,655	207,742
Fair Value
Without single maturity date	557,801
Available for sale, fair value	557,801	214,951
Commercial collateralized mortgage obligations
Amortized Cost
Without single maturity date	0
Fair Value
Without single maturity date	0
Amortized Cost
Without single maturity date	20,000
Available for sale, amortized cost	20,000
Fair Value
Without single maturity date	19,672
Available for sale, fair value	19,672
Residential collateralized mortgage obligations
Amortized Cost
Without single maturity date	0
Fair Value
Without single maturity date	0
Amortized Cost
Without single maturity date	196,691
Available for sale, amortized cost	196,691	193,865
Fair Value
Without single maturity date	193,740
Available for sale, fair value	193,740	195,343
Asset-backed securities
Amortized Cost
Without single maturity date	0
Fair Value
Without single maturity date	0
Amortized Cost
Without single maturity date	81,985
Available for sale, amortized cost	81,985	73,451
Fair Value
Without single maturity date	83,062
Available for sale, fair value	$ 83,062	$ 74,328

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