Derivative Liabilities and Collateral Pledged (Details) - USD ($)		Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015
Derivative [Line Items]
Gross amounts of recognized liabilities		$ 146,297,000	$ 108,339,000	$ 133,273,000
Derivative Liabilities not subject to master netting agreements		17,800,000		12,800,000
Derivatives, Interest Rate Contracts | Subject to Master Netting Agreements
Derivative [Line Items]
Gross amounts of recognized liabilities	[1]	128,448,000		120,429,000
Gross amounts offset in the Statement of Condition	[1]	0		0
Net amounts of liabilities presented in the Statement of Condition	[1],[2]	128,448,000		120,429,000
Derivative assets available for offset	[1]	(9,998,000)		(14,053,000)
Collateral pledged	[1]	(63,738,000)		(82,440,000)
Net amount	[1]	$ 54,712,000		$ 23,936,000

[1] 2016 and 2015 are comprised entirely of interest rate derivative contracts.

[2] In cluded in Derivative l iabilities on the Consolidated Condensed Statements of Condition. As of March 31 , 201 6 and 201 5 , $ 17 . 8 million and $ 12.8 million, respectively, of derivative liabilities (primarily fixed income forward contracts) have been excluded from these tables because they are generally not subject to master netting or similar agreements.