Fair Value Measurements - Financial and non-financial assets measured at fair value on a nonrecurring basis (Details) - Nonrecurring [Member] - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	$ 6,298	$ 9,018
Other real estate owned	5,073	3,345
Repossessed assets	843	1,043
Level I [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	0	0
Other real estate owned	0	0
Repossessed assets	0	0
Level II [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	0	0
Other real estate owned	0	0
Repossessed assets	0	0
Level III [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	6,298	9,018
Other real estate owned	5,073	3,345
Repossessed assets	$ 843	$ 1,043