Additional percentage of note principal due at redemption.

No definition available.

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- Definition

Minimum excess availability needed for 30 consecutive days to be in compliance with covenant.

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No definition available.

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- Definition

Debt Instrument, Covenant Compliance, Minimum Fixed Charge Coverage Ratio

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No definition available.

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Minimum line cap percentage needed for 30 consecutive days to be in compliance with covenant.

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Minimum amount of excess availability to be in compliance with covenant.

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No definition available.

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Minimum percent of line cap to be in compliance with covenant.

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- Definition

Percentage of principal amount redemption allowed.

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No definition available.

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Percentage price of original principal amount of debt at which debt is required to be redeemed by the issuer under certain changes in control events.

+ References

No definition available.

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The amount of cash paid for interest on extinguished debt during the period.

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The fee charged for any outstanding letters of credit issued under the revolving line of credit.

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No definition available.

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Maximum amount of revolving line of credit that can be used for issuance of letters of credit.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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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.

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

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

Date the debt instrument was issued, in CCYY-MM-DD format.

+ References

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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

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

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- Definition

Latest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

+ References

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Section 50
-Paragraph 3
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- Definition

Gross amount of debt extinguished.

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No definition available.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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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.

+ References

No definition available.

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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.

+ References

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The carrying value as of the balance sheet date of the noncurrent portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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-URI http://asc.fasb.org/extlink&oid=6517033

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- Definition

The cash outflow for incremental, external costs directly pertaining to an early extinguishment of debt, including legal costs and prepayment penalties, and excluding interest and repayment of debt principal.

+ References

No definition available.

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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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Debt (Narrative) (Details)		12 Months Ended
Debt (Narrative) (Details)	Sep. 15, 2016 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Sep. 14, 2016 USD ($)
Debt Instrument [Line Items]
Issued amount		$ 352,963,000
Loss on debt extinguishment		(12,529,000)	$ 0	$ 0
Payments of debt extinguishment costs		8,438,000	0	0
Payments of debt issuance costs		$ 7,011,000	3,567,000	$ 10,000
Maximum borrowing capacity	$ 375,000,000				$ 450,000,000
Maximum letters of credit issuance	$ 100,000,000				$ 75,000,000
Unused capacity, commitment fee percentage		0.25%
Revolving line of credit		$ 0
Letters of credit, amount outstanding		70,300,000
Long-term debt		$ 346,489,000	$ 402,993,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Minimum fixed charge coverage ratio		1.00
Minimum excess availability for 30 consecutive days		$ 33,300,000
Threshold for line cap percentage		0.10
Minimum line cap percentage for 30 consecutive days		0.10
Threshold for excess availability		$ 33,300,000
Revolving Credit Facility [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Outstanding letters of credit fee		0.0075
Revolving Credit Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Outstanding letters of credit fee		0.0125
Revolving Credit Facility [Member] \| Base Rate Option [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		0.25%
Revolving Credit Facility [Member] \| Base Rate Option [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		0.75%
Revolving Credit Facility [Member] \| LIBOR Rate Option [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		1.00%
Revolving Credit Facility [Member] \| LIBOR Rate Option [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		1.25%
Revolving Credit Facility [Member] \| LIBOR Rate Option [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		1.75%
Revolving Credit Facility [Member] \| Federal Funds Rate [Member] \| Base Rate Option [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		0.50%
Senior Notes Due 2024 [Member]
Debt Instrument [Line Items]
Issuance date	Sep. 15, 2016
Issued amount	$ 350,000,000
Maturity date	Oct. 01, 2024
Interest rate	5.50%
Change in control repurchase percentage		101.00%
Payments of debt issuance costs		$ 6,700,000
Senior Notes Due 2018 [Member]
Debt Instrument [Line Items]
Extinguishment of debt		$ 250,000,000
Effective interest percentage		9.00%
Interest paid on extinguished debt		$ 11,300,000
Loss on debt extinguishment		12,529,000
Payments of debt extinguishment costs		8,438,000
Write off of deferred debt issuance cost		$ 4,100,000
Other [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Effective interest percentage		4.30%
Other [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Effective interest percentage		7.00%
Other [Member] \| Secured By Equipment [Member]
Debt Instrument [Line Items]
Issued amount		$ 2,500,000
Maturity date range, end		Nov. 30, 2018
Other [Member] \| Secured By Property [Member]
Debt Instrument [Line Items]
Issued amount		$ 400,000
Maturity date		Feb. 28, 2021
Debt Instrument, Redemption, Period One [Member] \| Senior Notes Due 2024 [Member]
Debt Instrument [Line Items]
Additional redemption percentage	1.00%
Redemption price percentage	104.125%
Debt Instrument, Redemption, Period One [Member] \| Senior Notes Due 2024 [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt instrument redemption price percentage allowed	100.00%
Debt Instrument, Redemption, Period One [Member] \| Senior Notes Due 2024 [Member] \| Repayment From Equity Offering [Member]
Debt Instrument [Line Items]
Redemption price percentage	105.50%
Debt Instrument, Redemption, Period One [Member] \| Senior Notes Due 2024 [Member] \| Repayment From Equity Offering [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt instrument redemption price percentage allowed	40.00%
Debt Instrument, Redemption, Period Two [Member] \| Senior Notes Due 2024 [Member]
Debt Instrument [Line Items]
Redemption price percentage	103.00%
Debt Instrument, Redemption, Period Two [Member] \| Senior Notes Due 2024 [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt instrument redemption price percentage allowed	10.00%