Segment Reporting - Segment Revenue and Segment Profit (Loss) (Details) $ in Millions		12 Months Ended
		Dec. 31, 2015 USD ($) service_offering primaryreportablesegment	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Segment Reporting Information [Line Items]
Reportable segments, number | primaryreportablesegment		2
Revenue	[1]	$ 17,699	$ 19,153	$ 19,523
Finance income	[1]	346	387	483
Total Revenues	[1]	18,045	19,540	20,006
Depreciation and Amortization, excluding Amortization of Acquired Intangible Assets	[1],[2]	880	950	895
Interest expense	[1],[3]	353	377	403
Segment profit (loss)	[1]	1,058	1,833	1,802
Equity in net income of unconsolidated affiliates	[1]	135	160	169
Services Segment [Member]
Segment Reporting Information [Line Items]
Revenue	[1],[4]	10,065	10,519	10,412
Finance income	[1],[4]	72	65	67
Total Revenues	[1],[4]	10,137	10,584	10,479
Depreciation and Amortization, excluding Amortization of Acquired Intangible Assets	[1],[2],[4]	571	602	536
Interest expense	[1],[4]	20	18	19
Segment profit (loss)	[1],[4]	446	956	1,055
Equity in net income of unconsolidated affiliates	[1],[4]	27	32	34
Software Implementation Charge		389
Software Implementation Charge - Revenue Reversal		116
Software Implementation Charge - Cost of Goods Sold		273
Document Technology [Member]
Segment Reporting Information [Line Items]
Revenue	[1]	7,098	8,044	8,500
Finance income	[1]	267	314	408
Total Revenues	[1]	7,365	8,358	8,908
Depreciation and Amortization, excluding Amortization of Acquired Intangible Assets	[1],[2]	297	334	345
Interest expense	[1]	108	121	140
Segment profit (loss)	[1]	879	1,149	964
Equity in net income of unconsolidated affiliates	[1]	108	128	135
Other [Member]
Segment Reporting Information [Line Items]
Revenue	[1]	536	590	611
Finance income	[1]	7	8	8
Total Revenues	[1]	543	598	619
Depreciation and Amortization, excluding Amortization of Acquired Intangible Assets	[1],[2]	12	14	14
Interest expense	[1]	225	238	244
Segment profit (loss)	[1]	(267)	(272)	(217)
Equity in net income of unconsolidated affiliates	[1]	$ 0	$ 0	$ 0
Outsourcing Offerings [Member] | Services Segment [Member]
Segment Reporting Information [Line Items]
Services segment description of offerings | service_offering		2

[1] Asset information on a segment basis is not disclosed as this information is not separately identified and internally reported to our Chief Operating Decision Maker (CODM).

[2] Depreciation and amortization excludes amortization of intangible assets - see reconciliation below.

[3] Includes Equipment financing interest expense, as well as non-financing interest expense included in Other expenses, net in the Consolidated Statements of Income.

[4] Services segment results for 2015 include a charge of $389 related to our Health Enterprise platform implementations in California and Montana. $116 of the charge was recorded as a reduction to revenues and the remainder of $273 was recorded to Cost of outsourcing, maintenance and rentals.