Long Term Debt (Senior Credit Facility) (Details) - USD ($) |
1 Months Ended | 12 Months Ended | ||
|---|---|---|---|---|
Nov. 30, 2016 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Debt Instrument [Line Items] | ||||
| Debt issuance costs | $ 2,563,000 | $ 5,451,000 | $ 13,979,000 | |
| Loss on extinguishment of debt | 649,000 | 640,000 | $ 27,700,000 | |
| Long-term debt, gross | 1,415,631,000 | 1,373,783,000 | ||
| Letters of credit outstanding | 21,000,000 | |||
| Medium-term Notes | Senior Credit Facility | ||||
| Debt Instrument [Line Items] | ||||
| Loan fees and other expenses | $ 200,000 | 500,000 | ||
| Debt issuance costs | 400,000 | 3,900,000 | ||
| Loss on extinguishment of debt | 600,000 | 600,000 | ||
| Line of Credit | Senior Credit Facility | Revolving Credit Facility | ||||
| Debt Instrument [Line Items] | ||||
| Long-term debt, gross | 100,000,000 | $ 55,000,000 | ||
| Maximum borrowing capacity | 200,000,000 | |||
| Remaining borrowing capacity | $ 79,000,000 | |||
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- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. 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 Represents the charge against earnings during the period for commitment fees and debt issuance expenses. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The total amount of the contingent obligation under letters of credit outstanding as of the reporting date. No definition available.
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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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