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Multiemployer Plans - Narrative (Details) | 12 Months Ended
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Dec. 31, 2017 USD ($) plan | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($)
Multiemployer Plans [Line Items] |  |  |
Withdrawal liability | $ 0 | $ 0 | $ 0
Minimum | Multiemployer Plans, Pension |  |  |
Multiemployer Plans [Line Items] |  |  |
Number of plans | plan | 200 |  |
Domestic |  |  |
Multiemployer Plans [Line Items] |  |  |
Benefit obligation | $ 7,200,000 | 7,000,000 |
Domestic | Multiemployer Plans, Pension | Multiemployer Plan, Plan Information, Available |  |  |
Multiemployer Plans [Line Items] |  |  |
Contributions | 179,216,000 | 167,297,000 | 147,056,000
Domestic | Multiemployer Plans, Postretirement Benefit | Multiemployer Plan, Plan Information, Not Available |  |  |
Multiemployer Plans [Line Items] |  |  |
Contributions | $ 130,900,000 | $ 130,500,000 | 108,100,000
Domestic | Minimum |  |  |
Multiemployer Plans [Line Items] |  |  |
Discount rate | 3.50% | 3.80% |
Domestic | Minimum | Multiemployer Plans, Pension | Multiemployer Plan, Plan Information, Available |  |  |
Multiemployer Plans [Line Items] |  |  |
Contributions | $ 2,000,000 |  |
UK Plan | Multiemployer Plans, Pension | Multiemployer Plan, Plan Information, Not Available |  |  |
Multiemployer Plans [Line Items] |  |  |
Number of plans | plan | 2 |  |
Contributions | $ 100,000 | $ 200,000 | 200,000
Red Zone | Domestic | Minimum | Multiemployer Plans, Pension | Multiemployer Plan, Plan Information, Available |  |  |
Multiemployer Plans [Line Items] |  |  |
Contributions | 500,000 |  |
Orange or Yellow Zones | Domestic | Minimum | Multiemployer Plans, Pension | Multiemployer Plan, Plan Information, Available |  |  |
Multiemployer Plans [Line Items] |  |  |
Contributions | $ 1,000,000 |  |
UK Plan 1 | UK Plan | Multiemployer Plans, Pension | Multiemployer Plan, Plan Information, Not Available |  |  |
Multiemployer Plans [Line Items] |  |  |
Multiemployer Plans, Funded Status | At least 80 percent |  |
United Kingdom Subsidiary | UK Plan |  |  |
Multiemployer Plans [Line Items] |  |  |
Benefit obligation | $ 332,618,000 | $ 306,731,000 | 295,825,000
Discount rate | 2.50% | 2.70% |
Selling, General and Administrative Expenses | Domestic |  |  |
Multiemployer Plans [Line Items] |  |  |
Reclassification adjustment from AOCI, net of income taxes | $ 200,000 | $ 200,000 | 200,000
Selling, General and Administrative Expenses | United Kingdom Subsidiary | UK Plan |  |  |
Multiemployer Plans [Line Items] |  |  |
Reclassification adjustment from AOCI, net of income taxes | $ 2,300,000 | $ 1,700,000 | $ 2,000,000

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- Definition Multiemployer Plans, Number of Plans + References No definition available. + Details
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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of contributions made to multiemployer plan by employer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450702-114947 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (e)(1) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450691-114947 + Details
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- Definition Indicate whether the multiemployer plan is less than 65 percent funded, between 65 and less than 80 percent funded, or at least 80 percent funded. The acceptable values are: (1) "less than 65 percent", (2) "between 65 and less than 80 percent", (3) "at least 80 percent", and (4) "NA". A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 + Details
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- Definition Amount, after tax, of reclassification adjustment from accumulated other comprehensive (income) loss for net periodic benefit cost (credit) of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e637-108580 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e689-108580 + Details
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