Commitments and Contingencies - Insurance (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Commitment And Contingencies [Line Items]
Insurance and other non-current liabilities	$ 404,560	$ 342,356
Insurance Claims
Commitment And Contingencies [Line Items]
Gross amount accrued for insurance claims	272,900	254,700
Insurance and other non-current liabilities	210,100	200,000
Related insurance recoveries/receivables	56,500	50,400
Related insurance recoveries/receivables included in prepaid expenses and other current assets	300	400
Related insurance recoveries/receivables included in other assets net	56,200	$ 50,000
Atlantic Bridge Project Insurance Claim
Commitment And Contingencies [Line Items]
Related insurance recoveries/receivables	$ 26,700

Commitment And Contingencies [Line Items]

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- Definition

Amount due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy.

+ References

No definition available.

+ Details

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- Definition

Amount due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.8)
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- Definition

Carrying amount due after one year of the balance sheet date (or one operating cycle, if longer) of amount due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The amount needed to reflect the estimated ultimate cost of settling claims relating to insured events that have occurred on or before the balance sheet date, whether or not reported to the insurer at that date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 50
-Paragraph 3
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- Definition

Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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