Investments (Gross Unrealized Losses and Fair Values of Securities) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Schedule of Investments [Line Items]
Available-for-sale securities, continuous unrealized loss position, less than twelve months, fair value	$ 73,897	$ 98,642
Available-for-sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	1,129	2,063
Available-for-sale securities, continuous unrealized loss position, twelve months or longer, fair value	30,650	23,188
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	5,850	7,767
Held-to-maturity securities, continuous unrealized loss position, less than twelve months, fair value	31,432	27,918
Held-to-maturity securities, continuous unrealized loss position, less than 12 months, unrealized loss	353	598
Held-to-maturity securities, continuous unrealized loss position, twelve months or longer, fair value	3,781	0
Held-to-maturity securities, continuous unrealized loss position, 12 months or longer, unrealized loss	102	0
US government agencies [Member]
Schedule of Investments [Line Items]
Available-for-sale securities, continuous unrealized loss position, less than twelve months, fair value	24,424	24,253
Available-for-sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	576	747
Available-for-sale securities, continuous unrealized loss position, twelve months or longer, fair value	0	0
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	0	0
Residential mortgage-backed agencies [Member]
Schedule of Investments [Line Items]
Held-to-maturity securities, continuous unrealized loss position, less than twelve months, fair value	24,580	20,899
Held-to-maturity securities, continuous unrealized loss position, less than 12 months, unrealized loss	283	279
Held-to-maturity securities, continuous unrealized loss position, twelve months or longer, fair value	3,781	0
Held-to-maturity securities, continuous unrealized loss position, 12 months or longer, unrealized loss	102	0
Commercial mortgage-backed agencies [Member]
Schedule of Investments [Line Items]
Available-for-sale securities, continuous unrealized loss position, less than twelve months, fair value	22,827	51,604
Available-for-sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	187	757
Available-for-sale securities, continuous unrealized loss position, twelve months or longer, fair value	9,801	0
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	331	0
Held-to-maturity securities, continuous unrealized loss position, less than twelve months, fair value		4,684
Held-to-maturity securities, continuous unrealized loss position, less than 12 months, unrealized loss		149
Held-to-maturity securities, continuous unrealized loss position, twelve months or longer, fair value		0
Held-to-maturity securities, continuous unrealized loss position, 12 months or longer, unrealized loss		0
Collateralized mortgage obligations [Member]
Schedule of Investments [Line Items]
Available-for-sale securities, continuous unrealized loss position, less than twelve months, fair value	24,556	14,706
Available-for-sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	346	399
Available-for-sale securities, continuous unrealized loss position, twelve months or longer, fair value	3,707	0
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	54	0
Held-to-maturity securities, continuous unrealized loss position, less than twelve months, fair value	4,476
Held-to-maturity securities, continuous unrealized loss position, less than 12 months, unrealized loss	61
Held-to-maturity securities, continuous unrealized loss position, twelve months or longer, fair value	0
Held-to-maturity securities, continuous unrealized loss position, 12 months or longer, unrealized loss	0
Obligations of states and political subdivisions [Member]
Schedule of Investments [Line Items]
Available-for-sale securities, continuous unrealized loss position, less than twelve months, fair value	2,090	8,079
Available-for-sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	20	160
Available-for-sale securities, continuous unrealized loss position, twelve months or longer, fair value	2,795	2,934
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	50	91
Held-to-maturity securities, continuous unrealized loss position, less than twelve months, fair value	2,376	2,335
Held-to-maturity securities, continuous unrealized loss position, less than 12 months, unrealized loss	9	170
Held-to-maturity securities, continuous unrealized loss position, twelve months or longer, fair value	0	0
Held-to-maturity securities, continuous unrealized loss position, 12 months or longer, unrealized loss	0	0
Collateralized debt obligations [Member]
Schedule of Investments [Line Items]
Available-for-sale securities, continuous unrealized loss position, less than twelve months, fair value	0	0
Available-for-sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	0	0
Available-for-sale securities, continuous unrealized loss position, twelve months or longer, fair value	14,347	20,254
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	$ 5,415	$ 7,676