Securities (Fair value and gross unrealized losses) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Available-for-sale Securities
Less than 12 months, fair value	$ 87,323	$ 21,687
Less than 12 Months, Unrealized Loss	(1,461)	(77)
12 months or more, fair value	151,692	275,353
12 months or more, Unrealized Loss	(4,701)	(8,801)
Total, fair value	239,015	297,040
Total, Unrealized Loss	(6,162)	(8,878)
Held-to-maturity Securities
Less than 12 months, fair value	27,240	32,302
Less than 12 months, Unrealized Loss	(29)	(256)
12 months or more, fair value	117,134	171,736
12 months or more, Unrealized Loss	(3,131)	(6,114)
Total, fair value	144,374	204,038
Total, Unrealized Loss	(3,160)	(6,370)
U.S. Government agency securities [Member]
Held-to-maturity Securities
Less than 12 months, fair value	9,969	0
Less than 12 months, Unrealized Loss	(19)	0
12 months or more, fair value	100,751	144,454
12 months or more, Unrealized Loss	(2,193)	(4,658)
Total, fair value	110,720	144,454
Total, Unrealized Loss	(2,212)	(4,658)
Agency CMOs [Member]
Held-to-maturity Securities
Less than 12 months, fair value	17,271	31,289
Less than 12 months, Unrealized Loss	(10)	(255)
12 months or more, fair value	16,383	27,282
12 months or more, Unrealized Loss	(938)	(1,456)
Total, fair value	33,654	58,571
Total, Unrealized Loss	(948)	(1,711)
Municipal securities [Member]
Held-to-maturity Securities
Less than 12 months, fair value		1,013
Less than 12 months, Unrealized Loss		(1)
12 months or more, fair value		0
12 months or more, Unrealized Loss		0
Total, fair value		1,013
Total, Unrealized Loss		(1)
U.S. Government agency securities [Member]
Available-for-sale Securities
Less than 12 months, fair value	24,566	0
Less than 12 Months, Unrealized Loss	(435)	0
12 months or more, fair value	8,975	32,788
12 months or more, Unrealized Loss	(20)	(1,207)
Total, fair value	33,541	32,788
Total, Unrealized Loss	(455)	(1,207)
Residential mortgage-backed securities [Member]
Available-for-sale Securities
Less than 12 months, fair value	15,475	0
Less than 12 Months, Unrealized Loss	(117)	0
12 months or more, fair value	8,841	24,636
12 months or more, Unrealized Loss	(105)	(489)
Total, fair value	24,316	24,636
Total, Unrealized Loss	(222)	(489)
Agency CMOs [Member]
Available-for-sale Securities
Less than 12 months, fair value	45,320	21,687
Less than 12 Months, Unrealized Loss	(881)	(77)
12 months or more, fair value	131,560	212,908
12 months or more, Unrealized Loss	(4,522)	(6,987)
Total, fair value	176,880	234,595
Total, Unrealized Loss	(5,403)	(7,064)
Municipal securities [Member]
Available-for-sale Securities
Less than 12 months, fair value	1,962	0
Less than 12 Months, Unrealized Loss	(28)	0
12 months or more, fair value	2,316	5,021
12 months or more, Unrealized Loss	(54)	(118)
Total, fair value	4,278	5,021
Total, Unrealized Loss	$ (82)	$ (118)