Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI - Troubled Debt Restructuring Subsequently Defaulted (Details) - Troubled Debt Restructurings that Subsequently Defaulted [Member] $ in Thousands	6 Months Ended
	Jun. 30, 2019 USD ($) Contract	Jun. 30, 2018 USD ($) Contract
Troubled Debt Restructurings [Abstract]
Number of Contracts | Contract	12	6
Recorded Investment | $	$ 8,030	$ 7,466
Construction, Land Development and Other Land [Member]
Troubled Debt Restructurings [Abstract]
Number of Contracts | Contract	0	1
Recorded Investment | $	$ 0	$ 22
Secured by 1-4 Family Residential Properties [Member]
Troubled Debt Restructurings [Abstract]
Number of Contracts | Contract	1	2
Recorded Investment | $	$ 46	$ 30
Commercial and Industrial Loans [Member]
Troubled Debt Restructurings [Abstract]
Number of Contracts | Contract	10	3
Recorded Investment | $	$ 7,957	$ 7,414
Consumer Loans [Member]
Troubled Debt Restructurings [Abstract]
Number of Contracts | Contract	1	0
Recorded Investment | $	$ 27	$ 0