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Senior Debt (Details) - Feb. 13, 2015 - Senior Notes - 3.50% Senior Notes Due 2025 - USD ($)	Total
Long-term debt
Face amount	$ 350,000,000
Interest rate	3.50%

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: 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



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-Publisher FASB



-Name Accounting Standards Codification



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-SubTopic 30



-Section 45



-Paragraph 2



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- Definition

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

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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 210.5-02.22(a)(1))



-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682



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-Publisher SEC



-Name Regulation S-X (SX)



-Number 210



-Section 02



-Paragraph 22



-Article 5

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No definition available.

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