Employee Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Amortization of:
one-time non-cash charge			$ 7,700
Pension and other postretirement benefit plans, accumulated other comprehensive income (loss), net Transition Assets (Obligations), before Tax	$ 12,800		12,800
Contribution to pension plans			42,300
Estimated total contributions			80,000
Pension Benefits [Member]
Amortization of:
Net pension expense	21,177	$ 10,296	34,018	$ 20,814
Company Administered Plan [Member] | Pension Benefits [Member]
Components of net periodic benefit cost
Service cost	3,005	3,566	6,405	7,193
Interest cost	27,093	22,048	49,332	43,935
Expected return on plan assets	(22,667)	(25,021)	(45,752)	(49,921)
Amortization of:
Net actuarial loss	8,600	7,664	16,565	15,472
Prior service cost/(credit)	2,740	(74)	2,740	(150)
Net pension expense	18,771	8,183	29,290	16,529
Company Administered Plan [Member] | Pension Benefits U.S. [Member]
Amortization of:
Net pension expense	19,263	8,599	30,437	17,491
Company Administered Plan [Member] | Pension Benefits Non-U.S. [Member]
Amortization of:
Net pension expense	(492)	(416)	(1,147)	(962)
Union Administered Plan [Member] | Pension Benefits [Member]
Amortization of:
Net pension expense	$ 2,406	$ 2,113	$ 4,728	$ 4,285