Securities (Fair value and gross unrealized losses) (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Available-for-sale Securities
Less than 12 months, fair value	$ 81,245	$ 21,687
Less than 12 Months, Unrealized Loss	(1,116)	(77)
12 months or more, fair value	142,988	275,353
12 months or more, Unrealized Loss	(4,283)	(8,801)
Total, fair value	224,233	297,040
Total, Unrealized Loss	(5,399)	(8,878)
Held-to-maturity Securities
Less than 12 months, fair value	11,213	32,302
Less than 12 months, Unrealized Loss	(403)	(256)
12 months or more, fair value	117,207	171,736
12 months or more, Unrealized Loss	(2,151)	(6,114)
Total, fair value	128,420	204,038
Total, Unrealized Loss	(2,554)	(6,370)
U.S. Government agency securities [Member]
Available-for-sale Securities
Less than 12 months, fair value	24,727	0
Less than 12 Months, Unrealized Loss	(272)	0
12 months or more, fair value	8,967	32,788
12 months or more, Unrealized Loss	(30)	(1,207)
Total, fair value	33,694	32,788
Total, Unrealized Loss	(302)	(1,207)
Held-to-maturity Securities
Less than 12 months, fair value	0	0
Less than 12 months, Unrealized Loss	0	0
12 months or more, fair value	101,571	144,454
12 months or more, Unrealized Loss	(1,375)	(4,658)
Total, fair value	101,571	144,454
Total, Unrealized Loss	(1,375)	(4,658)
Residential mortgage-backed securities [Member]
Available-for-sale Securities
Less than 12 months, fair value	14,648	0
Less than 12 Months, Unrealized Loss	(206)	0
12 months or more, fair value	8,391	24,636
12 months or more, Unrealized Loss	(145)	(489)
Total, fair value	23,039	24,636
Total, Unrealized Loss	(351)	(489)
Agency CMOs [Member]
Available-for-sale Securities
Less than 12 months, fair value	39,929	21,687
Less than 12 Months, Unrealized Loss	(589)	(77)
12 months or more, fair value	123,337	212,908
12 months or more, Unrealized Loss	(4,031)	(6,987)
Total, fair value	163,266	234,595
Total, Unrealized Loss	(4,620)	(7,064)
Held-to-maturity Securities
Less than 12 months, fair value	9,364	31,289
Less than 12 months, Unrealized Loss	(377)	(255)
12 months or more, fair value	15,636	27,282
12 months or more, Unrealized Loss	(776)	(1,456)
Total, fair value	25,000	58,571
Total, Unrealized Loss	(1,153)	(1,711)
Municipal securities [Member]
Available-for-sale Securities
Less than 12 months, fair value	1,941	0
Less than 12 Months, Unrealized Loss	(49)	0
12 months or more, fair value	2,293	5,021
12 months or more, Unrealized Loss	(77)	(118)
Total, fair value	4,234	5,021
Total, Unrealized Loss	(126)	(118)
Held-to-maturity Securities
Less than 12 months, fair value	1,849	1,013
Less than 12 months, Unrealized Loss	(26)	(1)
12 months or more, fair value	0	0
12 months or more, Unrealized Loss	0	0
Total, fair value	1,849	1,013
Total, Unrealized Loss	$ (26)	$ (1)