Fair Value - Assets and Liabilities Measured on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Available for sale securities:
Securities available-for-sale, carried at fair value	$ 578,224	$ 283,448
Collateralized mortgage obligations [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	122,284	82,101
Fair Value, Inputs, Level 2 [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	578,224
Fair Value, Inputs, Level 2 [Member] | Collateralized mortgage obligations [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	122,284	82,101
Obligations of U.S. government corporations and agencies [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	40,926	2,524
Obligations of U.S. government corporations and agencies [Member] | Fair Value, Inputs, Level 2 [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	40,926	2,524
Mortgage-Backed Securities [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	215,639	89,647
Mortgage-Backed Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	215,639	89,647
Corporate bonds [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	29,988	12,101
Corporate bonds [Member] | Fair Value, Inputs, Level 2 [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	29,988	12,101
Obligations of state and political subdivisions [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	169,387	95,439
Obligations of state and political subdivisions [Member] | Fair Value, Inputs, Level 2 [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	169,387	92,028
Obligations of state and political subdivisions [Member] | Fair Value, Inputs, Level 3 [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value		3,411
Equity Securities [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	1,014
Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	1,014
Loans Held for Sale, at Fair Value [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	208,054
Loans Held for Sale, at Fair Value [Member] | Fair Value, Inputs, Level 2 [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	96,032
Loans Held for Sale, at Fair Value [Member] | Fair Value, Inputs, Level 3 [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	112,022
Purchased Certificate of Deposit Option [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	56
Purchased Certificate of Deposit Option [Member] | Fair Value, Inputs, Level 2 [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	56
Interest Rate Swap Assets [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	2,312
Interest Rate Swap Assets [Member] | Fair Value, Inputs, Level 2 [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	2,312
Mortgage banking derivative - asset [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	7,913	892
Mortgage banking derivative - asset [Member] | Fair Value, Inputs, Level 2 [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	7,913	892
Written Certificate of Deposit Option [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	56
Written Certificate of Deposit Option [Member] | Fair Value, Inputs, Level 2 [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	56
Interest Rate Swap Liability [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	2,560
Interest Rate Swap Liability [Member] | Fair Value, Inputs, Level 2 [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value	$ 2,560
REMICs [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value		1,636
REMICs [Member] | Fair Value, Inputs, Level 2 [Member]
Available for sale securities:
Securities available-for-sale, carried at fair value		$ 1,636