Consolidated Statements of Cash Flows (Parenthetical)	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
7 5/8% senior subordinated notes
Long-term debt and notes payable
Interest rate of debt (as a percent)	7.625%	7.625%	7.625%
6.375% senior notes
Long-term debt and notes payable
Interest rate of debt (as a percent)	6.375%	6.375%	6.375%

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

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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