Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI - Troubled Debt Restructuring Subsequently Defaulted (Details) - Troubled Debt Restructurings [Member] $ in Thousands	9 Months Ended
	Sep. 30, 2019 USD ($) Contract	Sep. 30, 2018 USD ($) Contract
Troubled Debt Restructurings [Abstract]
Number of Contracts | Contract	10	13
Recorded Investment | $	$ 327	$ 14,327
Construction, Land Development and Other Land [Member]
Troubled Debt Restructurings [Abstract]
Number of Contracts | Contract	0	1
Recorded Investment | $	$ 0	$ 21
Secured by 1-4 Family Residential Properties [Member]
Troubled Debt Restructurings [Abstract]
Number of Contracts | Contract	1	6
Recorded Investment | $	$ 46	$ 321
Commercial and Industrial Loans [Member]
Troubled Debt Restructurings [Abstract]
Number of Contracts | Contract	8	6
Recorded Investment | $	$ 254	$ 13,985
Consumer Loans [Member]
Troubled Debt Restructurings [Abstract]
Number of Contracts | Contract	1	0
Recorded Investment | $	$ 27	$ 0