Fair Value Measurements - (Inputs Used to Determine Fair Values of Oreo are Considered Level 3 Inputs in Fair Value Hierarchy) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Other Real Estate Owned [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets on a non-recurring basis	$ 11,875	$ 15,552
Losses From Fair Value Changes	38	46
Impaired loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets on a non-recurring basis	34,672	41,103
Losses From Fair Value Changes	$ 715	$ 209