Debt (Term Convertible Trust Securities) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	24 Months Ended
	Dec. 31, 2000	Dec. 31, 1999 security quarter
Debt Disclosure [Abstract]
Term convertible preferred securities issued by special purpose business trust		10,350,000
Current redemption value of term convertible preferred securities issued by special purpose business trust		$ 50
Term convertible preferred securities issued by special purpose business trust par per share		$ 0.844
Term convertible preferred securities issued by special purpose business trust total proceeds	$ 517
Junior subordinated convertible debentures purchased with proceeds from issuance of term convertible preferred securities		$ 517
Term convertible preferred securities dividend rate		6.75%
Term convertible preferred securities common stock conversion ratio	142.16%
Term convertible preferred securities common stock conversion price per share		$ 35.17
Maximum shares parent common stock issuance upon conversion		14.7
Term convertible preferred securities number of quarters dividends may be deferred		20