Basis of Presentation and Summary of Significant Accounting Policies - New Accounting Pronouncements (Details) - USD ($) |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2017 |
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2016 |
Sep. 30, 2016 |
Jun. 30, 2016 |
Mar. 31, 2016 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Item Effected [Line Items] | |||||||||||
| Goodwill, Impairment Loss | $ 89,000,000 | $ 0 | $ 0 | $ 78,000,000 | $ 64,000,000 | $ 0 | $ 0 | $ 0 | $ 167,000,000 | $ 64,000,000 | $ 0 |
| Other non-current assets | 9,118,000 | 7,233,000 | 9,118,000 | 7,233,000 | |||||||
| Long-term debt | $ 598,958,000 | $ 468,231,000 | $ 598,958,000 | $ 468,231,000 | |||||||
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- Definition Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Carrying value as of the balance sheet date of notes payable (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of noncurrent assets classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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