Subsidiary Guarantors Of Long-Term Debt (Condensed Consolidating Statement Of Cash Flows) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Schedule Of Subsidiary Guarantors Of Long Term Debt [Line Items]
Net cash provided by (used in) operating activities from continuing operations	$ 953	$ 958	$ 850
Capital expenditures, including capitalization of software costs	(192)	(175)	(198)
Payments for acquisitions of businesses, net of cash acquired	(511)	(9)
Other investing activities	38	59	(50)
Net cash (used in) provided by investing activities from continuing operations	(665)	(116)	(248)
(Repayments of) proceed from long-term debt, net	(37)	(312)	(475)
Purchases of treasury stock	(533)	(413)	(175)
Other financing activities	72	54	49
Net cash used in financing activities from continuing operations	(498)	(671)	(601)
Net change in cash and cash equivalents from continuing operations	(210)	171	1
Net cash flows from discontinued operations	(16)	29	94
Net cash transactions transferred (to) from discontinued operations	(16)	29	132
Beginning balance	563	363	230
Ending balance	337	563	363
Parent Company [Member]
Schedule Of Subsidiary Guarantors Of Long Term Debt [Line Items]
Net cash provided by (used in) operating activities from continuing operations	(10)	(4)	44
Capital expenditures, including capitalization of software costs	(13)	(6)	(3)
Other investing activities	311	939	(58)
Net cash (used in) provided by investing activities from continuing operations	298	933	(61)
(Repayments of) proceed from long-term debt, net	(80)	(308)	(471)
Purchases of treasury stock	(533)	(413)	(175)
Other financing activities	71	51	554
Net cash used in financing activities from continuing operations	(542)	(670)	(92)
Net change in cash and cash equivalents from continuing operations	(254)	259	(109)
Net cash flows from discontinued operations	(16)	29	132
Beginning balance	343	55	32
Ending balance	73	343	55
Guarantor Subsidiaries [Member]
Schedule Of Subsidiary Guarantors Of Long Term Debt [Line Items]
Net cash provided by (used in) operating activities from continuing operations	737	749	552
Capital expenditures, including capitalization of software costs	(144)	(135)	(155)
Payments for acquisitions of businesses, net of cash acquired	(473)
Other investing activities	45	22	(331)
Net cash (used in) provided by investing activities from continuing operations	(572)	(113)	(486)
(Repayments of) proceed from long-term debt, net	(3)	(4)
Other financing activities	(159)	(734)
Net cash used in financing activities from continuing operations	(162)	(738)
Net change in cash and cash equivalents from continuing operations	3	(102)	66
Beginning balance	68	170	104
Ending balance	71	68	170
Non-Guarantor Subsidiaries [Member]
Schedule Of Subsidiary Guarantors Of Long Term Debt [Line Items]
Net cash provided by (used in) operating activities from continuing operations	226	213	258
Capital expenditures, including capitalization of software costs	(35)	(34)	(41)
Payments for acquisitions of businesses, net of cash acquired	(38)
Other investing activities	(7)	24	(172)
Net cash (used in) provided by investing activities from continuing operations	(80)	(10)	(213)
(Repayments of) proceed from long-term debt, net	46		(4)
Other financing activities	(151)	(189)	3
Net cash used in financing activities from continuing operations	(105)	(189)	(1)
Net change in cash and cash equivalents from continuing operations	41	14	44
Beginning balance	152	138	94
Ending balance	193	152	138
Eliminations [Member]
Schedule Of Subsidiary Guarantors Of Long Term Debt [Line Items]
Net cash provided by (used in) operating activities from continuing operations			(4)
Capital expenditures, including capitalization of software costs			1
Other investing activities	(311)	(926)	511
Net cash (used in) provided by investing activities from continuing operations	(311)	(926)	512
Other financing activities	311	926	(508)
Net cash used in financing activities from continuing operations	$ 311	$ 926	$ (508)