Business Segment Information - Narrative (Details) - USD ($) |
3 Months Ended | 12 Months Ended |
|---|---|---|
Mar. 31, 2018 |
Dec. 31, 2017 |
|
| Segment Reporting Information [Line Items] | ||
| Unallocated corporate expense | $ 0 | |
| Customer Who Declared Bankruptcy | ||
| Segment Reporting Information [Line Items] | ||
| Unallocated corporate expense | $ 1,001,000 |
| X | ||||||||||
- Definition Unallocated Corporate Expense Segment No definition available.
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| X | ||||||||||
- 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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| X | ||||||||||
- Details
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