Investment Securities (Gross Unrealized Losses and Fair Value by Length of Continuous Unrealized Loss Position) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, continuous unrealized loss position, less than 12 months, fair value	$ 144,333	$ 134,172
Available-for-sale securities, continuous unrealized loss position, less than 12 Months, unrealized losses	3,514	1,153
Available-for-sale securities, continuous unrealized loss position, more than 12 Months, fair value	29,416	34,837
Available-for-sale securities, continuous unrealized loss position, more than 12 Months, unrealized losses	1,185	742
Available-for-sale securities, continuous unrealized loss position, fair value	173,749	169,009
Available-for-sale securities, continuous unrealized loss position, unrealized losses	4,699	1,895
Equity [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, continuous unrealized loss position, more than 12 Months, fair value		666
Available-for-sale securities, continuous unrealized loss position, more than 12 Months, unrealized losses		8
Available-for-sale securities, continuous unrealized loss position, fair value		666
Available-for-sale securities, continuous unrealized loss position, unrealized losses		8
U.S. Government Agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, continuous unrealized loss position, less than 12 months, fair value	37,263	37,550
Available-for-sale securities, continuous unrealized loss position, less than 12 Months, unrealized losses	740	453
Available-for-sale securities, continuous unrealized loss position, more than 12 Months, fair value	2,949	5,956
Available-for-sale securities, continuous unrealized loss position, more than 12 Months, unrealized losses	52	44
Available-for-sale securities, continuous unrealized loss position, fair value	40,212	43,506
Available-for-sale securities, continuous unrealized loss position, unrealized losses	792	497
Mortgage-backed [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, continuous unrealized loss position, less than 12 months, fair value	107,070	96,622
Available-for-sale securities, continuous unrealized loss position, less than 12 Months, unrealized losses	2,774	700
Available-for-sale securities, continuous unrealized loss position, more than 12 Months, fair value	26,467	28,215
Available-for-sale securities, continuous unrealized loss position, more than 12 Months, unrealized losses	1,133	690
Available-for-sale securities, continuous unrealized loss position, fair value	133,537	124,837
Available-for-sale securities, continuous unrealized loss position, unrealized losses	$ 3,907	$ 1,390