Debt (Summary Of Long Term Debt) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Long-term debt	$ 781,745	$ 735,267
Current portion of long-term debt	(8,527)	(8,776)
Long-term debt, less current portion	773,218	726,491
Term Loan Facility, Net Of Unamortized Issuance Costs, Maturing 2024 [Member]
Debt Instrument [Line Items]
Long-term debt	651,780	645,242
Unamortized debt issuance costs	7,200	7,500
Revolving Credit Facility, Maturing 2022 [Member]
Debt Instrument [Line Items]
Long-term debt	118,183	78,000
Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Long-term debt	4,776	4,913
Other Notes [Member]
Debt Instrument [Line Items]
Long-term debt	$ 7,006	$ 7,112

Current and noncurrent portions of long-term debt and capital lease obligations.

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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.

+ References

No definition available.

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- Definition

Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Principal amount of long-term debt and capital lease obligation maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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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