Fair Value Measurements (Fair Value Financial Assets Measured on Recurring Basis) (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	$ 469,720	$ 494,819
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	0	0
Interest rate swap derivatives	0	0
Total assets	0	0
Interest rate swap derivatives	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	469,720	494,819
Interest rate swap derivatives	3,053	5,239
Total assets	472,773	500,058
Interest rate swap derivatives	3,053	5,239
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	0	0
Interest rate swap derivatives	0	0
Total assets	0	0
Interest rate swap derivatives	$ 0	$ 0