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

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- Definition

Financial Instruments And Fair Value Measurements [Line Items]

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No definition available.

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- Definition

Carrying value as of the balance sheet date of all foreign currency derivatives not designated as hedging instruments.

+ References

No definition available.

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- Definition

Interest Rate Derivative Assets, at Carrying Value

+ References

No definition available.

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- Definition

Interest Rate Derivative Liabilities, at Carrying Value

+ References

No definition available.

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- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (a)
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-Publisher FASB
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

No definition available.

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13476-108611

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- Definition

Fair value as of the balance sheet date of all foreign currency derivatives not designated as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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- Definition

Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

+ References

+ Details

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- Definition

Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

+ References

+ Details

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Period Type:	instant

- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or 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(19)(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13))
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(1))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the amount of short-term debt existing as of the 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

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Financial Instruments (Financial Instruments Assets (Liabilities) Measured At Fair Value) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016
Financial Instruments And Fair Value Measurements [Line Items]
Cash and cash equivalents, Carrying Amount	$ 53,296	$ 63,551	$ 92,829	$ 45,582
Loans payable, Carrying Amount	(27,022)	(16,360)
Long-term debt, Carrying Amount	(781,745)	(735,267)
Foreign currency forward contracts, net, Carrying Amount	460	(469)
Cash and cash equivalents, Fair Value	53,296	63,551
Loans payable, Fair Value	(27,022)	(16,360)
Foreign currency forward contracts, net, Fair Value	460	(469)
Interest Rate Swap [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Interest Rate Swaps-Asset, Carrying Amount	3,392	1,616
Interest Rate Swaps-Liabilities, Carrying Amount	(191)	(124)
Interest Rate Swaps-Asset, Fair Value	3,392	1,616
Interest Rate Swaps-Liabilities, Fair Value	(191)	(124)
Revolving Credit Facility, Maturing 2022 [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Long-term debt, Carrying Amount	(118,183)	(78,000)
Long-term debt, Fair Value	(119,312)	(79,295)
Term Loan Facility, Net Of Unamortized Issuance Costs, Maturing 2021 [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Long-term debt, Carrying Amount		(645,242)
Long-term debt, Fair Value		(646,979)
Unamortized debt issuance costs	7,200	7,500
Term Loan Facility, Net Of Unamortized Issuance Costs, Maturing 2024 [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Long-term debt, Carrying Amount	(651,780)
Long-term debt, Fair Value	(653,410)
Other Long-Term Notes Payable [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Long-term debt, Carrying Amount	(7,006)	(7,112)
Long-term debt, Fair Value	(4,526)	(3,973)
Level 1 [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Cash and cash equivalents, Fair Value	53,296	63,551
Level 2 [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Loans payable, Fair Value	(27,022)	(16,360)
Foreign currency forward contracts, net, Fair Value	460	(469)
Level 2 [Member] \| Interest Rate Swap [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Interest Rate Swaps-Asset, Fair Value	3,392	1,616
Interest Rate Swaps-Liabilities, Fair Value	(191)	(124)
Level 2 [Member] \| Revolving Credit Facility, Maturing 2022 [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Long-term debt, Fair Value	(119,312)	(79,295)
Level 2 [Member] \| Term Loan Facility, Net Of Unamortized Issuance Costs, Maturing 2021 [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Long-term debt, Fair Value		(646,979)
Level 2 [Member] \| Term Loan Facility, Net Of Unamortized Issuance Costs, Maturing 2024 [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Long-term debt, Fair Value	(653,410)
Level 2 [Member] \| Other Long-Term Notes Payable [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Long-term debt, Fair Value	(4,526)	$ (3,973)
Level 3 [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Cash and cash equivalents, Fair Value
Loans payable, Fair Value
Foreign currency forward contracts, net, Fair Value
Level 3 [Member] \| Interest Rate Swap [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Interest Rate Swaps-Asset, Fair Value
Interest Rate Swaps-Liabilities, Fair Value
Level 3 [Member] \| Revolving Credit Facility, Maturing 2022 [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Long-term debt, Fair Value
Level 3 [Member] \| Term Loan Facility, Net Of Unamortized Issuance Costs, Maturing 2024 [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Long-term debt, Fair Value
Level 3 [Member] \| Other Long-Term Notes Payable [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Long-term debt, Fair Value