Subsequent Events (Details) - USD ($) |
1 Months Ended | 12 Months Ended | ||||
|---|---|---|---|---|---|---|
Jan. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
Feb. 26, 2018 |
Dec. 28, 2017 |
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| Subsequent Event [Line Items] | ||||||
| Borrowings against credit agreement | $ 2,000,000 | $ 0 | $ 0 | |||
| Financial covenants, minimum net worth | $ 200,000,000.0 | $ 230,000,000 | ||||
| Subsequent Event | ||||||
| Subsequent Event [Line Items] | ||||||
| Borrowings against credit agreement | $ 10,000,000 | |||||
| Financial covenants, minimum net worth | $ 185,000,000.0 | |||||
| Percent of gain on sale of assets added to net worth requirement | 50.00% | |||||
| X | ||||||||||
- Definition Debt Instrument, Covenant Terms, Percent Of Gain On Sale Of Assets Added To Net Worth Requirement No definition available.
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| X | ||||||||||
- Definition The lowest amount of net worth (total assets minus total liabilities) required by secondary market investors or state-imposed regulatory mandates. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event. No definition available.
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- Details
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