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Fair Value Measurements (Narrative) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Jan. 31, 2013
Extinguishment of Debt [Line Items]
Carrying value of outstanding debt	$ 210,405	$ 210,021
Senior Subordinated 6.25% Notes
Extinguishment of Debt [Line Items]
Senior Subordinated Notes, interest rate	6.25%	6.25%	6.25%
Carrying value of outstanding debt	$ 210,000	$ 210,000
Fair Value
Extinguishment of Debt [Line Items]
Fair value of debt, gross	$ 210,800	$ 213,800

X

- Definition

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

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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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- Definition

The fair value amount of long-term debt 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.

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