Long-term Debt	3 Months Ended
Jun. 30, 2011
Notes To Condensed Consolidated Financial Statements [Abstract]
Long-term Debt	6. Long-term Debt There have been no significant changes to long-term debt since December 31, 2010. In April 2011, we entered into two interest rate swap agreements with an aggregate notional value of $450 million to effectively convert the fixed rate interest payments on our $450 million 4.875% notes due in 2014 into variable rates. Under the terms of these agreements, we pay a weighted-average variable rate based on three month LIBOR plus 305 basis points and receive fixed rate payments of 4.875%.

The entire disclosure for long-term debt.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 22
-Article 5

Reference 2: 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)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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