Long-Term Debt (Schedule of Long-Term Debt) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2013
Debt Instrument [Line Items]
Total debt	$ 213,600,000us-gaap_LongTermDebt	$ 213,600,000us-gaap_LongTermDebt
Less current maturities	400,000us-gaap_LongTermDebtCurrent	400,000us-gaap_LongTermDebtCurrent
Total long-term debt	213,200,000us-gaap_LongTermDebtNoncurrent	213,200,000us-gaap_LongTermDebtNoncurrent
Senior Subordinated 6.25% Notes
Debt Instrument [Line Items]
Total debt	210,000,000	210,000,000
Senior Subordinated Notes, interest rate	6.25%		6.25%
Other debt
Debt Instrument [Line Items]
Total debt	$ 3,600,000	$ 3,600,000

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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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-Paragraph 22

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

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Amount of long-term debt, after unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Section S99

-Paragraph 1

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+ References

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

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