Loans and Allowance for Loan Losses - Purchased Credit Impaired Loans (Details) - Purchased Credit Impaired Loans [Member] - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Total loans	$ 32,499	$ 35,619
Less remaining purchase discount	(7,288)	(8,426)
Total loans, net of purchase discount	25,211	27,193
Less: Allowance for loan losses	0	0
Carrying amount, net of allowance	25,211	27,193
Commercial Real Estate [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Total loans	17,713	18,473
Consumer Real Estate [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Total loans	11,030	12,111
Construction and Land Development [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Total loans	1,778	2,553
Commercial and Industrial [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Total loans	1,978	2,482
Consumer and Other [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Total loans	$ 0	$ 0