Employee Benefit Plans - Obligations and Funded Status (Details)	12 Months Ended
	Dec. 31, 2017 USD ($) Participants	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan expense	$ 41,919,000	$ 34,665,000	$ 32,281,000
Document Fiscal Year Focus	2017
Number of participants covered by post retirement benefit plans | Participants	431
Number of participants eligible for medical benefits | Participants	411
Contributions to multiemployer plans	$ 2,000,000	2,000,000
Change in Benefit Obligation [Roll Forward]
Settlements and Curtailments	(3,844,000)	0	0
Assets and Liabilities [Abstract]
Other liabilities (deferred compensation)	(198,623,000)	(196,268,000)
Accumulated Other Comprehensive Loss (Earnings) [Abstract]
Total Accumulated Other Comprehensive Loss (Earnings), net of tax	100,538,000	121,925,000
Accumulated benefit obligation	908,656,000	845,896,000
Net periodic benefit cost [Abstract]
Settlement & curtailment (gain) loss	2,462,000	0	0
Total net periodic benefit cost	13,238,000	26,492,000	34,253,000
Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets [Abstract]
Projected benefit obligation (PBO)	372,559,000	346,710,000
Accumulated benefit obligation (ABO)	349,735,000	325,969,000
Fair value of plan assets	162,890,000	140,589,000
U.S. Pension Plan, Defined Benefit [Member]
Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year	535,299,000	527,667,000
Service cost	12,083,000	13,913,000	15,661,000
Interest cost	21,718,000	23,046,000	23,163,000
Plan participants' contributions	0	0
Benefits paid	(38,490,000)	(32,341,000)
Actuarial loss (gain)	35,446,000	2,980,000
Business (dispositions) acquisitions	0	0
Amendments	364,000	0
Settlements and Curtailments	(32,000)	0
Currency translation and other	1,000	34,000
Benefit obligation at end of year	566,389,000	535,299,000	527,667,000
Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	562,564,000	552,817,000
Actual return on plan assets	93,766,000	42,088,000
Company contributions	0	0
Plan participants' contributions	0	0
Benefits paid	(38,490,000)	(32,341,000)
Business (dispositions) acquisitions	0	0
Settlements and curtailments	0	0
Foreign currency translation	0	0
Fair value of plan assets at end of year	617,840,000	562,564,000	552,817,000
Defined Benefit Plan, Funded Status of Plan [Abstract]
Funded (Unfunded) status	51,451,000	27,265,000
Assets and Liabilities [Abstract]
Other assets and deferred charges	51,451,000	27,265,000
Accrued compensation and employee benefits	0	0
Other liabilities (deferred compensation)	0	0
Total Assets and Liabilities	51,451,000	27,265,000
Accumulated Other Comprehensive Loss (Earnings) [Abstract]
Net actuarial losses (gains)	79,288,000	103,410,000
Prior service cost (credit)	1,344,000	1,482,000
Net asset at transition, other	0	0
Deferred taxes	(30,777,000)	(36,712,000)
Total Accumulated Other Comprehensive Loss (Earnings), net of tax	49,855,000	68,180,000
Net amount recognized on the balance sheet	101,306,000	95,445,000
Accumulated benefit obligation	547,278,000	512,707,000
Net periodic benefit cost [Abstract]
Service cost	12,083,000	13,913,000	15,661,000
Interest cost	21,718,000	23,046,000	23,163,000
Expected return on plan assets	(39,812,000)	(38,793,000)	(41,571,000)
Amortization of prior service costs (income)	427,000	733,000	897,000
Amortization of actuarial (gains) losses	5,582,000	6,437,000	12,620,000
Amortization of transition obligation	0	0	0
Settlement & curtailment (gain) loss	76,000	0	810,000
Defined Benefit Plan, Other Costs	0	35,000	0
Total net periodic benefit cost	74,000	5,371,000	11,580,000
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year [Abstract]
Prior service cost (credit)	346,000
Recognized actuarial loss (gain)	7,725,000
Transition obligation	0
Amounts that will be amortized from accumulated other comprehensive earnings (loss) in next fiscal year	8,071,000
Non-U.S. Pension Plans, Defined Benefit [Member]
Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year	243,483,000	245,986,000
Service cost	5,688,000	5,590,000	6,613,000
Interest cost	5,263,000	5,593,000	5,885,000
Plan participants' contributions	1,237,000	1,223,000
Benefits paid	(8,528,000)	(7,870,000)
Actuarial loss (gain)	8,812,000	22,909,000
Business (dispositions) acquisitions	(1,810,000)	(4,420,000)
Amendments	0	0
Settlements and Curtailments	0	(3,262,000)
Currency translation and other	20,423,000	(22,266,000)
Benefit obligation at end of year	278,188,000	243,483,000	245,986,000
Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	148,514,000	159,436,000
Actual return on plan assets	15,849,000	10,317,000
Company contributions	7,971,000	8,383,000
Plan participants' contributions	1,237,000	1,223,000
Benefits paid	(8,528,000)	(7,870,000)
Business (dispositions) acquisitions	0	(3,967,000)
Settlements and curtailments	0	(3,262,000)
Foreign currency translation	10,491,000	(15,746,000)
Fair value of plan assets at end of year	175,534,000	148,514,000	159,436,000
Defined Benefit Plan, Funded Status of Plan [Abstract]
Funded (Unfunded) status	(102,654,000)	(94,969,000)
Assets and Liabilities [Abstract]
Other assets and deferred charges	1,002,000	706,000
Accrued compensation and employee benefits	(1,484,000)	(1,235,000)
Other liabilities (deferred compensation)	(102,172,000)	(94,440,000)
Total Assets and Liabilities	(102,654,000)	(94,969,000)
Accumulated Other Comprehensive Loss (Earnings) [Abstract]
Net actuarial losses (gains)	69,490,000	73,023,000
Prior service cost (credit)	(3,500,000)	(3,925,000)
Net asset at transition, other	(60,000)	(56,000)
Deferred taxes	(14,982,000)	(15,719,000)
Total Accumulated Other Comprehensive Loss (Earnings), net of tax	50,948,000	53,323,000
Net amount recognized on the balance sheet	(51,706,000)	(41,646,000)
Accumulated benefit obligation	264,766,000	231,903,000
Net periodic benefit cost [Abstract]
Service cost	5,688,000	5,590,000	6,613,000
Interest cost	5,263,000	5,593,000	5,885,000
Expected return on plan assets	(7,417,000)	(7,830,000)	(7,990,000)
Amortization of prior service costs (income)	(425,000)	(397,000)	89,000
Amortization of actuarial (gains) losses	3,506,000	2,658,000	2,647,000
Amortization of transition obligation	4,000	4,000	4,000
Settlement & curtailment (gain) loss	678,000	1,103,000	(184,000)
Defined Benefit Plan, Other Costs	0	0	0
Total net periodic benefit cost	7,297,000	6,721,000	7,064,000
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year [Abstract]
Prior service cost (credit)	(441,000)
Recognized actuarial loss (gain)	3,094,000
Transition obligation	4,000
Amounts that will be amortized from accumulated other comprehensive earnings (loss) in next fiscal year	2,657,000
Supplemental Employee Retirement Plans, Defined Benefit [Member]
Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year	110,446,000	125,311,000
Service cost	2,473,000	2,959,000	3,739,000
Interest cost	4,076,000	5,268,000	5,063,000
Plan participants' contributions	0	0
Benefits paid	(11,576,000)	(16,643,000)
Actuarial loss (gain)	593,000	(6,449,000)
Business (dispositions) acquisitions	0	0
Amendments	0	0
Settlements and Curtailments	0	0
Currency translation and other	0	0
Benefit obligation at end of year	106,012,000	110,446,000	125,311,000
Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0	0
Actual return on plan assets	0	0
Company contributions	11,576,000	16,643,000
Plan participants' contributions	0	0
Benefits paid	(11,576,000)	(16,643,000)
Business (dispositions) acquisitions	0	0
Settlements and curtailments	0	0
Foreign currency translation	0	0
Fair value of plan assets at end of year	0	0	0
Defined Benefit Plan, Funded Status of Plan [Abstract]
Funded (Unfunded) status	(106,012,000)	(110,446,000)
Assets and Liabilities [Abstract]
Other assets and deferred charges	0	0
Accrued compensation and employee benefits	(17,450,000)	(20,032,000)
Other liabilities (deferred compensation)	(88,562,000)	(90,414,000)
Total Assets and Liabilities	(106,012,000)	(110,446,000)
Accumulated Other Comprehensive Loss (Earnings) [Abstract]
Net actuarial losses (gains)	(13,780,000)	(15,565,000)
Prior service cost (credit)	13,777,000	18,187,000
Net asset at transition, other	0	0
Deferred taxes	83,000	(920,000)
Total Accumulated Other Comprehensive Loss (Earnings), net of tax	80,000	1,702,000
Net amount recognized on the balance sheet	(105,932,000)	(108,744,000)
Accumulated benefit obligation	96,612,000	101,286,000
Net periodic benefit cost [Abstract]
Service cost	2,473,000	2,959,000	3,739,000
Interest cost	4,076,000	5,268,000	5,063,000
Expected return on plan assets	0	0	0
Amortization of prior service costs (income)	4,411,000	6,266,000	6,927,000
Amortization of actuarial (gains) losses	(1,192,000)	(560,000)	286,000
Amortization of transition obligation	0	0	0
Settlement & curtailment (gain) loss	0	0	0
Defined Benefit Plan, Other Costs	0	0	0
Total net periodic benefit cost	9,768,000	13,933,000	16,015,000
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year [Abstract]
Prior service cost (credit)	3,852,000
Recognized actuarial loss (gain)	(1,020,000)
Transition obligation	0
Amounts that will be amortized from accumulated other comprehensive earnings (loss) in next fiscal year	2,832,000
Other Postretirement Benefit Plans, Defined Benefit [Member]
Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year	12,263,000	10,885,000
Service cost	68,000	52,000	163,000
Interest cost	783,000	403,000	512,000
Plan participants' contributions	0	102,000
Benefits paid	(917,000)	(767,000)
Actuarial loss (gain)	946,000	(2,343,000)
Business (dispositions) acquisitions	0	(4,367,000)
Amendments	(4,646,000)	0
Settlements and Curtailments	0	0
Currency translation and other	98,000	(436,000)
Benefit obligation at end of year	8,595,000	12,263,000	10,885,000
Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0	0
Actual return on plan assets	0	0
Company contributions	917,000	665,000
Plan participants' contributions	0	102,000
Benefits paid	(917,000)	(767,000)
Business (dispositions) acquisitions	0	0
Settlements and curtailments	0	0
Foreign currency translation	0	0
Fair value of plan assets at end of year	0	0	0
Defined Benefit Plan, Funded Status of Plan [Abstract]
Funded (Unfunded) status	(8,595,000)	(12,263,000)
Assets and Liabilities [Abstract]
Other assets and deferred charges	0	0
Accrued compensation and employee benefits	(706,000)	(849,000)
Other liabilities (deferred compensation)	(7,889,000)	(11,414,000)
Total Assets and Liabilities	(8,595,000)	(12,263,000)
Accumulated Other Comprehensive Loss (Earnings) [Abstract]
Net actuarial losses (gains)	(748,000)	(1,921,000)
Prior service cost (credit)	84,000	43,000
Net asset at transition, other	0	0
Deferred taxes	322,000	598,000
Total Accumulated Other Comprehensive Loss (Earnings), net of tax	(342,000)	(1,280,000)
Net amount recognized on the balance sheet	(8,937,000)	(13,543,000)
Net periodic benefit cost [Abstract]
Service cost	68,000	52,000	163,000
Interest cost	783,000	403,000	512,000
Amortization of prior service costs (income)	7,000	7,000	(372,000)
Amortization of actuarial (gains) losses	(161,000)	5,000	(30,000)
Settlement & curtailment (gain) loss	(4,598,000)	0	0
Other pension costs	0	0	(679,000)
Total net periodic benefit cost	(3,901,000)	$ 467,000	$ (406,000)
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year [Abstract]
Prior service cost (credit)	13,000
Recognized actuarial loss (gain)	(30,000)
Transition obligation	0
Amounts that will be amortized from accumulated other comprehensive earnings (loss) in next fiscal year	$ (17,000)