Discontinued Operations - Summary of Assets and Liabilities Held for Sale Related to Discontinued Operations (Detail) - USD ($) $ in Millions	Sep. 30, 2015	Jun. 30, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net assets held for sale	$ 5	$ 92
Digital Education [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Current assets	61	54
Non-current assets	17	100
Total assets	78	154
Current Liabilities	60	46
Non-current liabilities	13	16
Total liabilities	73	62
Net assets held for sale	$ 5	$ 92