CONDENSED CONSOLIDATED BALANCE SHEET (Parenthetical) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Common stock, shares issued	128.1us-gaap_CommonStockSharesIssued	128.0us-gaap_CommonStockSharesIssued
Common stock held in treasury, shares	30.6us-gaap_TreasuryStockShares	29.8us-gaap_TreasuryStockShares

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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 210.5-02.29)

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

Name:	us-gaap_CommonStockSharesIssued
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant