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SUPPLEMENTAL FINANCIAL STATEMENT INFORMATION (Valuation Accounts) (Details) (USD $)
In Millions, unless otherwise specified
Sep. 30, 2013
Dec. 31, 2012
Jun. 30, 2013
National Envelope [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]      
Accumulated depreciation $ 19,826 $ 18,934  
Allowance for doubtful accounts 138 119 28
Accounts Receivable, Net, Current     $ 42