Legal Proceedings (Details) (USD $) In Millions	Jun. 30, 2011
Legal Proceedings
Maximum amount of loss that is reasonably possible, in excess of the amount accrued	$ 5

The difference between the maximum amount of estimated loss and the amount recorded as of the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 14
-Paragraph 3

Name:	us-gaap_LossContingencyRangeOfPossibleLossPortionNotAccrued
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant