Investment Securities (Details 2) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Available-for-sale
Less than twelve months, estimated fair value	$ 34,021	$ 249,273
Less than twelve months, unrealized losses	140	2,329
Twelve months or longer, estimated fair value	44,057	118,847
Twelve months or longer, unrealized losses	556	3,720
Total, estimated fair value	78,078	368,120
Total, unrealized losses	696	6,049
Held-to-maturity
Less than twelve months, estimated fair value	19,100	52,300
Less than twelve months, unrealized losses	52	435
Twelve months or longer, estimated fair value	0	0
Twelve months or longer, unrealized losses	0	0
Total, estimated fair value	19,100	52,300
Total, unrealized losses	52	435
Available-for-sale and Held-to-maturity
Less than twelve months, estimated fair value	53,121	301,573
Less than twelve months, unrealized losses	192	2,764
Twelve months or longer, estimated fair value	44,057	118,847
Twelve months or longer, unrealized losses	556	3,720
Total, estimated fair value	97,178	420,420
Total, unrealized losses	748	6,484
GSE debentures
Available-for-sale
Less than twelve months, estimated fair value	6,126	19,633
Less than twelve months, unrealized losses	13	172
Twelve months or longer, estimated fair value	0	0
Twelve months or longer, unrealized losses	0	0
Total, estimated fair value	6,126	19,633
Total, unrealized losses	13	172
Held-to-maturity
Less than twelve months, estimated fair value	11,702	25,837
Less than twelve months, unrealized losses	32	105
Twelve months or longer, estimated fair value	0	0
Twelve months or longer, unrealized losses	0	0
Total, estimated fair value	11,702	25,837
Total, unrealized losses	32	105
GSE CMOs
Available-for-sale
Less than twelve months, estimated fair value	19,232	89,680
Less than twelve months, unrealized losses	88	1,294
Twelve months or longer, estimated fair value	42,424	100,473
Twelve months or longer, unrealized losses	396	2,935
Total, estimated fair value	61,656	190,153
Total, unrealized losses	484	4,229
GSE MBSs
Available-for-sale
Less than twelve months, estimated fair value	6,142	133,779
Less than twelve months, unrealized losses	23	845
Twelve months or longer, estimated fair value	246	16,968
Twelve months or longer, unrealized losses	4	585
Total, estimated fair value	6,388	150,747
Total, unrealized losses	27	1,430
Held-to-maturity
Less than twelve months, estimated fair value	4,462	18,834
Less than twelve months, unrealized losses	6	305
Twelve months or longer, estimated fair value	0	0
Twelve months or longer, unrealized losses	0	0
Total, estimated fair value	4,462	18,834
Total, unrealized losses	6	305
SBA commercial loan asset-backed securities
Available-for-sale
Less than twelve months, estimated fair value	29	0
Less than twelve months, unrealized losses	0	0
Twelve months or longer, estimated fair value	74	139
Twelve months or longer, unrealized losses	1	1
Total, estimated fair value	103	139
Total, unrealized losses	1	1
Corporate debt obligations
Available-for-sale
Less than twelve months, estimated fair value	2,492	6,181
Less than twelve months, unrealized losses	16	18
Twelve months or longer, estimated fair value	0	0
Twelve months or longer, unrealized losses	0	0
Total, estimated fair value	2,492	6,181
Total, unrealized losses	16	18
Trust preferred securities
Available-for-sale
Less than twelve months, estimated fair value	0	0
Less than twelve months, unrealized losses	0	0
Twelve months or longer, estimated fair value	1,313	1,267
Twelve months or longer, unrealized losses	155	199
Total, estimated fair value	1,313	1,267
Total, unrealized losses	155	199
Municipal obligations
Held-to-maturity
Less than twelve months, estimated fair value	2,445	7,629
Less than twelve months, unrealized losses	5	25
Twelve months or longer, estimated fair value	0	0
Twelve months or longer, unrealized losses	0	0
Total, estimated fair value	2,445	7,629
Total, unrealized losses	5	$ 25
Foreign government obligations
Held-to-maturity
Less than twelve months, estimated fair value	491
Less than twelve months, unrealized losses	9
Twelve months or longer, estimated fair value	0
Twelve months or longer, unrealized losses	0
Total, estimated fair value	491
Total, unrealized losses	$ 9