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Securities - Schedule of Amortized Cost and Fair Value of Debt Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Available-for-sale Securities Debt Maturities, Amortized Cost [Abstract]
Available-for-sale Securities, Due in one year or less, Amortized Cost	$ 51,901
Available-for-sale Securities, Due from one to five years, Amortized Cost	99,605
Available-for-sale Securities, Due from five to ten years, Amortized Cost	136,479
Available-for-sale Securities, Due after ten years, Amortized Cost	104,697
Available-for-sale Securities, Amortized Cost	1,183,404	$ 834,254
Held-to-maturity Securities Debt Maturities, Amortized Cost [Abstract]
Held-to-maturity Securities, Due from one to five years, Amortized Cost	3,800
Held-to-maturity Securities, Due from five to ten years, Amortized Cost	612
Held-to-maturity Securities, Amortized Cost	4,412	99,266
Available-for-sale Securities Debt Maturities, Fair Value [Abstract]
Available-for-sale Securities, Due in one year or less, Fair Value	52,093
Available-for-sale Securities, Due from one to five years, Fair Value	100,593
Available-for-sale Securities, Due from five to ten years, Fair Value	137,843
Available-for-sale Securities, Due after ten years, Fair Value	104,730
Available-for-sale Securities, Fair Value, Total	1,186,292	817,656
Held-to-maturity Securities Debt Maturities, Fair Value [Abstract]
Held-to-maturity Securities, Due from one to five years, Fair Value	3,866
Held-to-maturity Securities, Due from five to ten years, Fair Value	632
Held-to-maturity securities, Fair Value, Total	4,498	$ 97,739
Mortgage and Asset-Backed Securities
Available-for-sale Securities Debt Maturities, Amortized Cost [Abstract]
Available-for-sale Securities, Not due at single maturity, Amortized Cost	790,722
Available-for-sale Securities Debt Maturities, Fair Value [Abstract]
Available-for-sale Securities, Not due at single maturity, Fair Value	$ 791,033

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