Defined Benefit Plans - Defined Benefit Plans Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Recognized Net Gain (Loss) Due to Settlements and Curtailments	$ 0	$ 0	$ 0	$ 0
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Recognized Net Gain (Loss) Due to Settlements and Curtailments	2,750	$ 0	2,750	$ 0
Defined Benefit Plan, Estimated Future Employer Contributions in Current Fiscal Year			3,500
Defined Benefit Plan, Contributions by Employer	$ 1,900		$ 2,600