Divestitures (Details) $ in Millions			3 Months Ended			9 Months Ended
		Aug. 01, 2017 USD ($)	Sep. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)	Mar. 04, 2016 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Separation costs			$ 1		$ 39	$ 9	$ 75
Total Costs and Expenses			2,330		2,463	7,174	7,648
Income (loss) from discontinued operations, net of tax			3		8	(3)	(65)
Interest expense	[1]		62		74	188	235
Proceeds from Conduent			0		0	161	0
Conduent [Domain]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenues			0		1,587	0	4,855
Cost of services			0		1,317	0	4,069
Other expenses(1)	[2]		1		286	9	897
Total Costs and Expenses			1		1,603	9	4,966
Net loss before income taxes			(1)		(16)	(9)	(111)
Income tax benefit			4		24	6	46
Income (loss) from discontinued operations, net of tax			$ 3		8	$ (3)	(65)
Interest expense					$ 6		$ 13
Proceeds from Conduent				$ 161
Conduent Cash Balance at Separation								$ 225
Disposal Date						Dec. 31, 2016
Naver [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Date		Aug. 01, 2017
Sales price of disposal group or unit		$ 23
Net assets and expenses sold		10
Goodwill sold		6
Gain on sale of business, pre-tax		13
Gain on sale of business, net of tax		$ 4
Employees transferred in sale		80
Senior Debt Obligations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Unsecured Debt									$ 1,000

[1] Includes Cost of financing as well as non-financing interest expense that is included in Other expenses, net in the Condensed Consolidated Statements of Income.

[2] The three and nine months ended September 30, 2016 include $6 and $13, respectively, of interest on the $1.0 billion Senior Unsecured Term Facility, which was required to be repaid upon completion of the Separation and therefore was reported in the Income (loss) from discontinued operations.