Investment Securities (Continuous Unrealized Loss Position) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013 securities	Dec. 31, 2012 securities
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, estimated fair value	$ 232,060	$ 129,971
Less than 12 months, gross unrealized losses	17,408	1,342
12 months or more, estimated fair value	97,940	11,293
12 months or more, gross unrealized losses	9,083	77
Total, estimated fair value	330,000	141,264
Total, gross unrealized losses	26,491	1,419
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, estimated fair value	141,125
Less than 12 months, gross unrealized losses	10,670
12 months or more, estimated fair value	0
12 months or more, gross unrealized losses	0
Total, estimated fair value	141,125
Total, gross unrealized losses	10,670
Continuous Unrealized Loss Position [Abstract]
Less than 12 months, estimated fair value	373,185
Less than 12 months, gross unrealized losses	28,078
12 months or more, estimated fair value	97,940
12 months or more, gross unrealized losses	9,083
Total, estimated fair value	471,125
Total, gross unrealized losses	37,161
12 months or more, number of securities	10	4
Residential mortgage-backed securities - GSE [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, estimated fair value	222,475	123,489
Less than 12 months, gross unrealized losses	16,585	904
12 months or more, estimated fair value	76,501	7,027
12 months or more, gross unrealized losses	7,755	44
Total, estimated fair value	298,976	130,516
Total, gross unrealized losses	24,340	948
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, estimated fair value	131,817
Less than 12 months, gross unrealized losses	9,907
12 months or more, estimated fair value	0
12 months or more, gross unrealized losses	0
Total, estimated fair value	131,817
Total, gross unrealized losses	9,907
Residential mortgage-backed securities - Private [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, estimated fair value	0	6,482
Less than 12 months, gross unrealized losses	0	438
12 months or more, estimated fair value	0	1,017
12 months or more, gross unrealized losses	0	16
Total, estimated fair value	0	7,499
Total, gross unrealized losses	0	454
Commercial mortgage-backed securities - GSE [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, estimated fair value	0
Less than 12 months, gross unrealized losses	0
12 months or more, estimated fair value	21,439
12 months or more, gross unrealized losses	1,328
Total, estimated fair value	21,439
Total, gross unrealized losses	1,328
Commercial mortgage-backed securities - Private [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, estimated fair value	9,585
Less than 12 months, gross unrealized losses	823
12 months or more, estimated fair value	0
12 months or more, gross unrealized losses	0
Total, estimated fair value	9,585
Total, gross unrealized losses	823
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, estimated fair value	9,308
Less than 12 months, gross unrealized losses	763
12 months or more, estimated fair value	0
12 months or more, gross unrealized losses	0
Total, estimated fair value	9,308
Total, gross unrealized losses	763
Corporate notes [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, estimated fair value		0
Less than 12 months, gross unrealized losses		0
12 months or more, estimated fair value		3,249
12 months or more, gross unrealized losses		17
Total, estimated fair value		3,249
Total, gross unrealized losses		$ 17