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, 2013		Dec. 31, 2012
Financial instruments owned:
Assets, Fair Value Disclosure	$ 202		$ 628
Fiduciary Assets:
Fiduciary Assets, Fair Value Disclosure	0		152
Liabilities:
Financial and Nonfinancial Liabilities, Fair Value Disclosure	357		319
Identical Assets (Level 1) [Member]
Financial instruments owned:
Assets, Fair Value Disclosure	199		622
Fiduciary Assets:
Fiduciary Assets, Fair Value Disclosure	0		149
Observable Inputs (Level 2) [Member]
Financial instruments owned:
Assets, Fair Value Disclosure	3		6
Fiduciary Assets:
Fiduciary Assets, Fair Value Disclosure	0		3
Liabilities:
Financial and Nonfinancial Liabilities, Fair Value Disclosure	253		256
Unobservable Inputs (Level 3) [Member]
Liabilities:
Financial and Nonfinancial Liabilities, Fair Value Disclosure	104		63
Other Assets [Member]
Financial instruments owned:
Other Assets, Fair Value Disclosure	154	[1]	139	[1]
Other Assets [Member] | Identical Assets (Level 1) [Member]
Financial instruments owned:
Other Assets, Fair Value Disclosure	154	[1]	139	[1]
Cash and Cash Equivalents [Member]
Financial instruments owned:
Cash and Cash Equivalents, Fair Value Disclosure	45	[2]	483	[2]
Cash and Cash Equivalents [Member] | Identical Assets (Level 1) [Member]
Financial instruments owned:
Cash and Cash Equivalents, Fair Value Disclosure	45	[2]	483	[2]
Other Receivables [Member]
Financial instruments owned:
Interest rate swap derivatives	3	[3]	6
Other Receivables [Member] | Observable Inputs (Level 2) [Member]
Financial instruments owned:
Interest rate swap derivatives	3	[3]	6	[3]
Accounts Payable and Accrued Liabilities and Other Liabilities [Member]
Liabilities:
Contingent purchase consideration liability, Fair Value Disclosure	104	[4]	63	[4]
Accounts Payable and Accrued Liabilities and Other Liabilities [Member] | Unobservable Inputs (Level 3) [Member]
Liabilities:
Contingent purchase consideration liability, Fair Value Disclosure	104	[4]	63	[4]
US States and US and Foreign Local Debt Securities [Member]
Fiduciary Assets:
Fiduciary Assets, Fair Value Disclosure	0		3
US States and US and Foreign Local Debt Securities [Member] | Observable Inputs (Level 2) [Member]
Fiduciary Assets:
Fiduciary Assets, Fair Value Disclosure	0		3
Money Market Funds [Member]
Fiduciary Assets:
Fiduciary Assets, Fair Value Disclosure	0		149
Money Market Funds [Member] | Identical Assets (Level 1) [Member]
Fiduciary Assets:
Fiduciary Assets, Fair Value Disclosure	0		149
Senior Debt Obligations Due 2014 [Member] | Long-term Debt [Member]
Liabilities:
Debt Instrument, Fair Value Disclosure	253	[5]	256	[5]
Senior Debt Obligations Due 2014 [Member] | Long-term Debt [Member] | Observable Inputs (Level 2) [Member]
Liabilities:
Debt Instrument, Fair Value Disclosure	$ 253	[5]	$ 256	[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.