Segment, Other Supplemental Information and Concentrations - Revenue by Product and Services (Detail) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting [Abstract]
Products (software and hardware)									$ 1,057	$ 1,227	$ 1,230
Consulting services									780	817	818
Maintenance services									693	688	644
Total services									1,473	1,505	1,462
Total revenue	$ 719	$ 606	$ 623	$ 582	$ 761	$ 667	$ 676	$ 628	$ 2,530	$ 2,732	$ 2,692