Senior Notes (Schedule Of Outstanding Senior Notes) (Details) (USD $)		3 Months Ended
May 24, 2013	Mar. 31, 2014 Senior Notes [Member]	Dec. 31, 2013 Senior Notes [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Debt instrument, stated interest rate		5.40%
Date issued		Oct. 12, 2004
Date due		Oct. 15, 2014
Principal amounts	$ 329,897,000	$ 250,000,000
Consolidated balance sheet amount		249,971,000	249,958,000
Market value		$ 256,500,000	$ 259,130,000

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Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

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-Publisher FASB

-Name Accounting Standards Codification

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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.

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-Publisher FASB

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- Definition

Interest rate stated in the contractual debt agreement.

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- Definition

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

+ References

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

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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