Investment Securities - Schedule of contractual maturity of debt securities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Investment [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	$ 1,727,363	$ 1,007,834
Debt Securities, Available-for-sale	1,754,140	1,059,341
Obligations of States and Political Subdivisions
Investment [Line Items]
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	197,895
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	$ 213,154
Debt Securities, Available-for-sale, Maturity, after Five Through Ten Years, Weighted Average Yield	3.75%
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost	$ 169,038
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	$ 176,437
Debt Securities, Available-for-sale, Maturity, after 10 Years, Weighted Average Yield	2.91%
Debt Securities, Available-for-sale, Amortized Cost	$ 366,933	279,245
Debt Securities, Available-for-sale	$ 389,591	305,218
Available for Sale Securities Weighted Avg Yield	3.36%
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Investment [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	$ 849,114	726,589
Debt Securities, Available-for-sale	$ 854,463	752,109
Debt Securities, Available-for-Sale, Weighted Average Yield	1.73%
Corporate Debt Securities
Investment [Line Items]
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	$ 11,250
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	$ 11,412
Debt Securities, Available-for-sale, Maturity, after Five Through Ten Years, Weighted Average Yield	3.93%
Debt Securities, Available-for-sale, Amortized Cost	$ 11,250	2,000
Debt Securities, Available-for-sale	11,412	$ 2,014
Collateralized Loan Obligations
Investment [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	500,066
Debt Securities, Available-for-sale	$ 498,674
Debt Securities, Available-for-Sale, Weighted Average Yield	1.61%

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