Condensed Consolidated Statement of Changes in Equity (Parenthetical) (Unaudited) (USD $) In Millions, unless otherwise specified	6 Months Ended
Jun. 30, 2012
Condensed Consolidated Statement Of Changes In Equity [Abstract]
Net income attributable to noncontrolling interest-redeemable	$ 3.6

Amount of Net Income (Loss) attributable to redeemable noncontrolling interest.

No definition available.

Name:	us-gaap_NetIncomeLossAttributableToRedeemableNoncontrollingInterest
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration