Commitments and Contingent Liabilities (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Commitments and Contingencies Disclosure [Abstract]
Rent expense for operating leases	$ 87,149	$ 76,541	$ 66,118
Accrual for environmental loss contingencies	32,890	34,031
Leases, Operating [Abstract]
Operating Lease 2015	63,979
Operating Lease 2016	51,193
Operating Lease 2017	42,647
Operating Lease 2018	33,297
Operating Lease 2019	24,283
Operating Lease 2020 and thereafter	57,536
Leases, Capital [Abstract]
Capital Lease 2015	3,801
Capital Lease 2016	2,015
Capital Lease 2017	731
Capital Lease 2018	196
Capital Lease 2019	112
Capital Lease 2020 and thereafter	347
Operating Leases, Future Minimum Payments Due	272,935
Capital Leases, Future Minimum Payments Due	$ 7,202