Derivative Liabilities and Collateral Pledged (Details) - USD ($) $ in Thousands		Sep. 30, 2016	Dec. 31, 2015	Sep. 30, 2015
Derivative [Line Items]
Gross amounts of recognized liabilities		$ 144,829	$ 108,339	$ 140,965
Derivative Liabilities not subject to master netting agreements		17,500		20,700
Derivatives, Interest Rate Contracts | Subject to Master Netting Agreements
Derivative [Line Items]
Gross amounts of recognized liabilities	[1]	127,352		120,234
Gross amounts offset in the Statement of Condition	[1]	0		0
Net amounts of liabilities presented in the Statement of Condition	[1],[2]	127,352		120,234
Derivative assets available for offset	[1]	(8,823)		(9,748)
Collateral pledged	[1]	(57,298)		(78,211)
Net amount	[1]	$ 61,231		$ 32,275

[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 September 30 , 2016 and 2015 , $ 17 . 5 million and $ 20.7 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.