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Debt (Narrative) (Details) - USD ($) |  | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Dec. 09, 2015 | Jan. 31, 2014 | Jan. 31, 2013 | Mar. 31, 2013 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Debt Instrument [Line Items] |  |  |  |  |  |  |
Standby letters of credit |  |  |  |  | $ 20,459,000 |  |
Availability amount |  |  |  |  | 279,541,000 |  |
Credit facility amount outstanding |  |  |  |  | 0 | $ 0 |
Fixed charge coverage ratio | 450.00% |  |  |  |  |  |
Paid placement and other fees |  |  |  |  | $ 1,166,000 | $ 35,000 | $ 3,899,000
Dividend payment restrictions, annual limit per share |  | $ 0.25 |  |  |  |  |
Dividend payment restrictions, aggregate annual limit |  | $ 25,000,000 |  |  |  |  |
Senior Credit Agreement |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Fixed charge coverage ratio | 325.00% |  |  |  |  |  |
Minimum interest coverage ratio | 300.00% |  |  |  |  |  |
Senior Subordinated 8% Notes, Due December 1, 2015 |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate |  |  | 8.00% |  |  |  |
Repurchase amount |  |  | $ 204,000,000 |  |  |  |
Repurchase charge |  |  |  | $ 7,166,000 |  |  |
Prepayment premium paid |  |  |  | 3,702,000 |  |  |
Write off of deferred financing costs |  |  |  | 2,199,000 |  |  |
Unamortized original issue discount |  |  |  | 1,265,000 |  |  |
Senior Subordinated 6.25% Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Notes issued |  |  | $ 210,000,000 |  |  |  |
Interest rate |  |  | 6.25% |  | 6.25% | 6.25% |
Paid placement and other fees |  |  |  | $ 3,755,000 |  |  |
Senior Subordinated 6.25% Notes | Change in Control |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Purchase price of the principal amount, percentage |  | 101.00% |  |  |  |  |
Senior Subordinated 6.25% Notes | On and After February 1, 2019 |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Redemption price, percentage of principal amount |  | 100.00% |  |  |  |  |
Senior Subordinated 6.25% Notes | Prior to February 1, 2016 |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Redemption price, percentage of principal amount |  | 106.25% |  |  |  |  |
Redemption percentage of aggregate principal amount |  | 35.00% |  |  |  |  |
Senior Subordinated 6.25% Notes | Minimum | 12-Month Redemption Period Beginning February 1, 2018 |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Redemption price percentage |  | 101.56% |  |  |  |  |
Senior Subordinated 6.25% Notes | Maximum | 12-Month Redemption Period Beginning February 1, 2017 |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Redemption price percentage |  | 103.13% |  |  |  |  |
Revolving Credit Facility | Senior Credit Agreement |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Current borrowing capacity | $ 300,000,000 |  |  |  |  |  |
Maximum borrowing capacity under the revolving credit facility | $ 500,000,000 |  |  |  |  |  |
Revolving Credit Facility | Senior Credit Agreement | Minimum |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Annual commitment fee | 0.20% |  |  |  |  |  |
Revolving Credit Facility | Senior Credit Agreement | Minimum | LIBOR |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
LIBOR floor, plus | 1.25% |  |  |  |  |  |
Revolving Credit Facility | Senior Credit Agreement | Maximum |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Annual commitment fee | 0.30% |  |  |  |  |  |
Revolving Credit Facility | Senior Credit Agreement | Maximum | LIBOR |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
LIBOR floor, plus | 2.25% |  |  |  |  |  |
Term Loan | Senior Credit Agreement |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Term loan (up to) | $ 200,000,000 |  |  |  |  |  |

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- Definition The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400 + Details
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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 20, 22 -Article 5 + Details
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- Definition The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used. + References No definition available. + Details
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- Definition Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility. + 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(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 + Details
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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. + 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(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 + Details
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