Fair Value Disclosures - Assets Measured at Fair Value on Non-recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Fair Value, Assets Measured on Recurring and Nonrecurring Basis [Line Items]
Other real estate owned	$ 540	$ 1,200
Total assets	1,725		$ 1,847
Fair Value, Nonrecurring [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans held for investment	22,663	25,166
Other real estate owned	540	1,187
Total assets	23,203	26,353
Fair Value, Nonrecurring [Member] | Level 1 [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans held for investment	0	0
Other real estate owned	0	0
Total assets	0	0
Fair Value, Nonrecurring [Member] | Level 2 [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans held for investment	0	0
Other real estate owned	0	0
Total assets	0	0
Fair Value, Nonrecurring [Member] | Level 3 [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans held for investment	22,663	25,166
Other real estate owned	540	1,187
Total assets	$ 23,203	$ 26,353