Health Care, Pension and Other Benefits (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Domestic Defined Benefit Pension Plans [Member]
Net periodic benefit cost (credit):
Service cost	$ 5,754	$ 5,636	$ 17,263	$ 16,910
Interest cost	6,236	6,526	18,710	19,577
Expected return on assets	(13,023)	(12,666)	(39,071)	(37,997)
Amortization of:
Prior service cost (credit)	327	459	982	1,377
Actuarial loss	844		2,530
Net periodic benefit cost (credit)	138	(45)	414	(133)
Foreign Defined Benefit Pension Plans [Member]
Net periodic benefit cost (credit):
Service cost	1,326	1,547	3,976	4,642
Interest cost	2,271	2,695	6,813	8,083
Expected return on assets	(2,431)	(2,739)	(7,292)	(8,219)
Amortization of:
Actuarial loss	485	356	1,454	1,067
Net periodic benefit cost (credit)	1,651	1,859	4,951	5,573
Postretirement Benefits Other than Pensions [Member]
Net periodic benefit cost (credit):
Service cost	621	609	1,863	1,826
Interest cost	2,795	3,195	8,386	9,586
Amortization of:
Prior service cost (credit)	(1,132)	(126)	(3,396)	(377)
Actuarial loss	253		759
Net periodic benefit cost (credit)	$ 2,537	$ 3,678	$ 7,612	$ 11,035