Condensed Consolidating Statement of Cash Flows (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Cash flows from operating activities:
Net cash provided by (used in) operating activities from continuing operations	$ 548	$ 681
Cash flows from investing activities:
Capital expenditures, including capitalization of software costs	(146)	(144)
Payments for acquisitions of businesses, net of cash acquired		(511)
Net proceeds from sale (purchases) of investments	27	(4)
Other investing activities	(3)	42
Net cash (used in) provided by investing activities from continuing operations	(122)	(617)
Cash flows from financing activities:
Proceeds from long-term debt	994	1,189
Repayments of long-term debt, including premium and costs	(946)	(1,105)
Purchases of treasury stock	(580)	(484)
Other financing activities	81	61
Net cash used in financing activities from continuing operations	(451)	(339)
Net change in cash and cash equivalents from continuing operations	(25)	(275)
Net cash flows from discontinued operations	(5)	(7)
Beginning balance	337	563
Ending balance	307	281
Parent Company
Cash flows from operating activities:
Net cash provided by (used in) operating activities from continuing operations	(158)	(19)
Cash flows from investing activities:
Capital expenditures, including capitalization of software costs	(3)	(12)
Other investing activities	538	116
Net cash (used in) provided by investing activities from continuing operations	535	104
Cash flows from financing activities:
Proceeds from long-term debt	994	1,143
Repayments of long-term debt, including premium and costs	(897)	(1,103)
Purchases of treasury stock	(580)	(484)
Other financing activities	79	61
Net cash used in financing activities from continuing operations	(404)	(383)
Net change in cash and cash equivalents from continuing operations	(27)	(298)
Net cash flows from discontinued operations	(5)	(7)
Beginning balance	73	343
Ending balance	41	38
Guarantor Subsidiaries
Cash flows from operating activities:
Net cash provided by (used in) operating activities from continuing operations	523	558
Cash flows from investing activities:
Capital expenditures, including capitalization of software costs	(107)	(113)
Payments for acquisitions of businesses, net of cash acquired		(473)
Net proceeds from sale (purchases) of investments	3	2
Other investing activities	(1)	42
Net cash (used in) provided by investing activities from continuing operations	(105)	(542)
Cash flows from financing activities:
Repayments of long-term debt, including premium and costs	(4)	(2)
Other financing activities	(431)	(16)
Net cash used in financing activities from continuing operations	(435)	(18)
Net change in cash and cash equivalents from continuing operations	(17)	(2)
Beginning balance	71	68
Ending balance	54	66
Non-Guarantor Subsidiaries
Cash flows from operating activities:
Net cash provided by (used in) operating activities from continuing operations	183	142
Cash flows from investing activities:
Capital expenditures, including capitalization of software costs	(36)	(19)
Payments for acquisitions of businesses, net of cash acquired		(38)
Net proceeds from sale (purchases) of investments	24	(6)
Other investing activities		1
Net cash (used in) provided by investing activities from continuing operations	(12)	(62)
Cash flows from financing activities:
Proceeds from long-term debt		46
Repayments of long-term debt, including premium and costs	(45)
Other financing activities	(107)	(101)
Net cash used in financing activities from continuing operations	(152)	(55)
Net change in cash and cash equivalents from continuing operations	19	25
Beginning balance	193	152
Ending balance	212	177
Eliminations
Cash flows from investing activities:
Other investing activities	(540)	(117)
Net cash (used in) provided by investing activities from continuing operations	(540)	(117)
Cash flows from financing activities:
Other financing activities	540	117
Net cash used in financing activities from continuing operations	$ 540	$ 117