Investment Securities (Details 4)	9 Months Ended
	Sep. 30, 2016 USD ($) security	Sep. 30, 2015 USD ($)	Dec. 31, 2015 USD ($) security
Schedule of Held-to-maturity Securities [Line Items]
Investment securities held-to-maturity, fair value	$ 78,079,000		$ 93,695,000
Net unrealized gain (loss), held-to-maturity securities	1,000,000		(62,000)
Purchases of investment securities held-to-maturity	25,045,000	$ 68,454,000
Gross Unrealized Gains	1,037,000		373,000
Held-to-maturity Securities	77,094,000		93,757,000
GSE debentures
Schedule of Held-to-maturity Securities [Line Items]
Investment securities held-to-maturity, fair value	$ 14,705,000		$ 34,819,000
Number of securities | security	6		12
Net unrealized gain (loss), held-to-maturity securities	$ (29,000)		$ (96,000)
Number of securities in an unrealized loss position | security	4		9
Purchases of investment securities held-to-maturity	$ 17,700,000	26,900,000
Gross Unrealized Gains	3,000		$ 9,000
Held-to-maturity Securities	14,734,000		34,915,000
GSE MBSs
Schedule of Held-to-maturity Securities [Line Items]
Investment securities held-to-maturity, fair value	$ 18,752,000		$ 18,986,000
Number of securities | security	11		10
Net unrealized gain (loss), held-to-maturity securities	$ 42,000		$ (300,000)
Number of securities in an unrealized loss position | security	2		7
Purchases of investment securities held-to-maturity	$ 2,400,000	21,300,000
Gross Unrealized Gains	48,000		$ 0
Held-to-maturity Securities	18,710,000		19,291,000
Municipal obligations
Schedule of Held-to-maturity Securities [Line Items]
Investment securities held-to-maturity, fair value	$ 44,131,000		$ 39,390,000
Number of securities | security	84		72
Net unrealized gain (loss), held-to-maturity securities	$ 1,000,000		$ 300,000
Number of securities in an unrealized loss position | security	6		15
Purchases of investment securities held-to-maturity	$ 4,400,000	20,300,000
Gross Unrealized Gains	986,000		$ 364,000
Held-to-maturity Securities	43,150,000		39,051,000
Foreign government obligations
Schedule of Held-to-maturity Securities [Line Items]
Investment securities held-to-maturity, fair value	$ 491,000		$ 500,000
Number of securities | security	1		1
Number of securities in an unrealized loss position | security	1		0
Purchases of investment securities held-to-maturity		$ 0
Gross Unrealized Gains	$ 0		$ 0
Held-to-maturity Securities	$ 500,000		$ 500,000
Number of HTM securities purchased | security	1