Company Recorded Restructuring Charges (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Restructuring Reserve [Roll Forward]
Balance as of January 1	$ 3	$ 12	$ 11
Restructuring charges	76		67
Restructuring Reserve, Settled with Cash	(29)	(9)	(48)
Restructuring Reserve, Settled without Cash	(22)		(18)
Balance as of December 31	28	3	12
Agent conversion charges [Member]
Restructuring Reserve [Roll Forward]
Balance as of January 1		6
Restructuring charges	6		30
Restructuring Reserve, Settled with Cash		(6)	(24)
Restructuring Reserve, Settled without Cash	3
Balance as of December 31	9		6
Asset impairment charges [Member]
Restructuring Reserve [Roll Forward]
Restructuring charges	25		18
Restructuring Reserve, Settled without Cash	(25)		(18)
Severance and related costs [Member]
Restructuring Reserve [Roll Forward]
Balance as of January 1	1	3	9
Restructuring charges	38		13
Restructuring Reserve, Settled with Cash	(29)	(2)	(19)
Balance as of December 31	10	1	3
Contractual obligations and other charges [Member]
Restructuring Reserve [Roll Forward]
Balance as of January 1	2	3	2
Restructuring charges	7		6
Restructuring Reserve, Settled with Cash		(1)	(5)
Balance as of December 31	$ 9	$ 2	$ 3