Change in Unrecognized Tax Benefits (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013
Income Tax Disclosure [Abstract]
Estimated unrecognized tax benefit decrease, lower bound	$ 30.0
Estimated unrecognized tax benefit decrease, upper bound	$ 40.0

The estimated lower bound of the reasonably possible change in the total amount of the unrecognized tax benefit (that will significantly increase or decrease within twelve months of the balance sheet date) for a tax position taken.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319

Name:	us-gaap_SignificantChangeInUnrecognizedTaxBenefitsIsReasonablyPossibleEstimatedRangeOfChangeLowerBound
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant