Employee Benefit Plans - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2014	Mar. 31, 2014	Jun. 30, 2015	Dec. 31, 2014
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Prepayments and other	$ 22,419				$ 22,419	$ 27,445
Pension Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Anticipated contributions by employer					13,700
Benefit payments made in current fiscal year					10,900
Additional benefit payments within the next 12 months	100				100
Settlement charges	700	$ 200
Settlement charges expensed			$ 400	$ 6,900
Settlement charges in discontinued operations			3,700
Non-Qualified Supplemental Employee Retirement Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Settlement charges		$ 2,500	$ 400
Rabbi Trust
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Prepayments and other	$ 3,300				$ 3,300