Fair Value Measurements - Schedule of Assets with Unobservable Inputs (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Nonrecurring assets	$ 14,207	$ 10,922
Nonrecurring assets, loss	1,942	457	$ 630
Level 1 inputs
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Nonrecurring assets	0	0
Level 2 inputs
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Nonrecurring assets	0	0
Level 3 inputs
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Nonrecurring assets	14,207	10,922
Loans measured for impairment
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Nonrecurring assets	7,988	9,222
Nonrecurring assets, loss	352	270	269
Loans measured for impairment | Level 1 inputs
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Nonrecurring assets	0	0
Loans measured for impairment | Level 2 inputs
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Nonrecurring assets	0	0
Loans measured for impairment | Level 3 inputs
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Nonrecurring assets	7,988	9,222
Other real estate owned
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Nonrecurring assets	3,927	1,700
Nonrecurring assets, loss	904	187	361
Other real estate owned | Level 1 inputs
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Nonrecurring assets	0	0
Other real estate owned | Level 2 inputs
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Nonrecurring assets	0	0
Other real estate owned | Level 3 inputs
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Nonrecurring assets	3,927	1,700
Other assets - equity method investment
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Nonrecurring assets	2,292
Nonrecurring assets, loss	686	$ 0	$ 0
Other assets - equity method investment | Level 1 inputs
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Nonrecurring assets	0
Other assets - equity method investment | Level 2 inputs
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Nonrecurring assets	0
Other assets - equity method investment | Level 3 inputs
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Nonrecurring assets	$ 2,292