Derivative Financial Instruments Balance Sheet Offsetting (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Offsetting Assets and Liabilities [Line Items]
Gross asset	$ 41,636	$ 33,398
Financial Instruments	(15,358)	(202)
Cash collateral	0	0
Net asset	26,278	33,196
Gross liability	41,842	33,117
Financial Instruments	(15,358)	(202)
Cash Collateral	(4,216)	(31,130)
Net liability	22,268	1,785
Interest Rate Swap
Offsetting Assets and Liabilities [Line Items]
Gross asset	41,395	32,970
Financial Instruments	(15,117)	(55)
Cash collateral	0	0
Net asset	26,278	32,915
Gross liability	41,395	32,970
Financial Instruments	(15,117)	(55)
Cash Collateral	(4,010)	(31,130)
Net liability	22,268	1,785
Foreign Exchange Contract
Offsetting Assets and Liabilities [Line Items]
Gross asset	241	428
Financial Instruments	(241)	(147)
Cash collateral	0	0
Net asset	0	281
Gross liability	447	147
Financial Instruments	(241)	(147)
Cash Collateral	(206)	0
Net liability	$ 0	$ 0