Fair Value Measurements (Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Details) (Fair Value, Measurements, Recurring [Member], USD $) In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Financial instruments owned:
Total assets measured at fair value	$ 257		$ 202
Fiduciary Assets:
Fiduciary assets	57		0
Liabilities:
Total liabilities measured at fair value	207		357
Identical Assets (Level 1) [Member]
Financial instruments owned:
Total assets measured at fair value	257		199
Fiduciary Assets:
Fiduciary assets	57		0
Liabilities:
Total liabilities measured at fair value	0		0
Observable Inputs (Level 2) [Member]
Financial instruments owned:
Total assets measured at fair value	0		3
Fiduciary Assets:
Fiduciary assets	0		0
Liabilities:
Total liabilities measured at fair value	0		253
Unobservable Inputs (Level 3) [Member]
Fiduciary Assets:
Fiduciary assets	0
Liabilities:
Total liabilities measured at fair value	207		104
Other Assets [Member]
Financial instruments owned:
Mutual funds	150	[1]	154	[1]
Other Assets [Member] | Identical Assets (Level 1) [Member]
Financial instruments owned:
Mutual funds	150	[1]	154	[1]
Cash and Cash Equivalents [Member]
Financial instruments owned:
Money market funds	107	[2]	45	[2]
Cash and Cash Equivalents [Member] | Identical Assets (Level 1) [Member]
Financial instruments owned:
Money market funds	107	[2]	45	[2]
Other Receivables [Member]
Financial instruments owned:
Interest rate swap derivatives	0	[3]	3
Other Receivables [Member] | Observable Inputs (Level 2) [Member]
Financial instruments owned:
Interest rate swap derivatives	0	[3]	3	[3]
Accounts Payable and Accrued Liabilities and Other Liabilities [Member]
Liabilities:
Contingent purchase consideration liability	207	[4]	104	[4]
Accounts Payable and Accrued Liabilities and Other Liabilities [Member] | Unobservable Inputs (Level 3) [Member]
Liabilities:
Contingent purchase consideration liability	207	[4]	104	[4]
Money Market Funds [Member]
Fiduciary Assets:
Fiduciary assets	57		0
Money Market Funds [Member] | Identical Assets (Level 1) [Member]
Fiduciary Assets:
Fiduciary assets	57		0
Senior Debt Obligations Due 2014 [Member] | Long-term Debt [Member]
Liabilities:
Senior Notes due 2014	0	[5]	253	[5]
Senior Debt Obligations Due 2014 [Member] | Long-term Debt [Member] | Observable Inputs (Level 2) [Member]
Liabilities:
Senior Notes due 2014	$ 0	[5]	$ 253	[5]

[1] Included in other assets in the consolidated balance sheets.

[2] Included in cash and cash equivalents in the consolidated balance sheets.

[3] Included in other receivables in the consolidated balance sheets.

[4] Included in accounts payable and accrued liabilities and other liabilities in the consolidated balance sheets

[5] Included in long-term debt in the consolidated balance sheets.