CONDENSED CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY (Parenthetical) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Mar. 31, 2015	Mar. 31, 2014
Shares issued during the year (less than 5 million shares)	5
Convertible subordinated notes—4 percent \| Convertible senior notes
Stated interest rate		4.00%	4.00%

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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