Valuation Allowance (Details) (USD $) In Billions	Dec. 31, 2010	Jun. 30, 2010
Valuation Allowance
Deferred tax assets valuation allowance	$ 3.0	$ 3.2

The sum of the portions of deferred tax assets as of the balance sheet date for which, based on the weight of available evidence, it is more likely than not will not be realized through future reductions of tax-based income.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 17
-Subparagraph e

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 43-49

Name:	us-gaap_DeferredTaxAssetsValuationAllowance
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant