Health Care, Pension and Other Benefits (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Domestic Defined Benefit Pension Plans [Member]
Net periodic benefit cost (credit):
Service cost	$ 5,489	$ 5,754
Interest cost	6,643	6,237
Expected return on assets	(12,567)	(13,024)
Amortization of:
Prior service cost (credit)	301	327
Actuarial loss	1,152	843
Net periodic benefit cost (credit)	1,018	137
Foreign Defined Benefit Pension Plans [Member]
Net periodic benefit cost (credit):
Service cost	1,341	1,325
Interest cost	2,080	2,271
Expected return on assets	(1,846)	(2,431)
Amortization of:
Actuarial loss	361	485
Settlement costs	4,038
Net periodic benefit cost (credit)	5,974	1,650
Postretirement Benefits Other than Pensions [Member]
Net periodic benefit cost (credit):
Service cost	561	621
Interest cost	2,752	2,795
Amortization of:
Prior service cost (credit)	(1,645)	(1,132)
Actuarial loss		253
Net periodic benefit cost (credit)	$ 1,668	$ 2,537