Income Taxes - Newsday and Chicago Cubs Transactions (Details) - USD ($) $ in Millions	3 Months Ended				6 Months Ended
	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Dec. 31, 2016	Oct. 27, 2009
New Cubs LLC
Income Tax Contingency [Line Items]
Ownership percentage in common stock by third party						95.00%
Ownership percentage in common stock						5.00%
Income taxes paid	$ 45
Deferred tax liability	155	$ 158			$ 158
New Cubs LLC | Tax Year 2009
Income Tax Contingency [Line Items]
IRS proposed tax	182
IRS proposed gross valuation misstatement penalty	73
After-tax interest on proposed tax and penalty	42
Estimated federal income taxes before interest and penalties	225
Newsday LLC
Income Tax Contingency [Line Items]
Net Adjustment to Uncertain Tax Position, Current				$ 102
Income tax reserves				125
Reduction in deferred income tax liabilities				23
Adjustment to deferred taxes		1	$ (3)	$ 91
Payment for income tax, interest and penalties					122
Expected future payment for income tax, interest and penalties	4	$ 4			$ 4
Newsday LLC | Tax Year 2008
Income Tax Contingency [Line Items]
Estimated federal income taxes before interest and penalties	190
IRS, accuracy-related penalty	$ 38