Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $) In Millions, except Share data	Sep. 30, 2011	Dec. 31, 2010
Operating Assets and Facilities
VIE for Rail	$ 5,652.7	$ 5,513.6
VIE depreciation allowance	2,061.2	2,049.7
Debt
VIE nonrecourse debt	157.8	217.2
Shareholders' Equity
Common stock, par value	$ 0.625	$ 0.625
Common stock, shares authorized	120,000,000	120,000,000
Common stock, shares issued	65,718,449	65,482,950
Common stock, shares outstanding	46,595,929	46,360,430
Treasury stock, shares outstanding	19,122,520	19,122,520
Variable Interest, Held by Entity [Member]
Operating Assets and Facilities
VIE for Rail	123.5	123.7
VIE depreciation allowance	17.8	13.6
Debt
VIE nonrecourse debt	48.1	56.2
Series A and B $2.50 Cumulative Convertible Preferred Stock
Shareholders' Equity
Preferred stock, par value	$ 1.00	$ 1.00
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	16,644	16,694
Preferred stock, shares outstanding	16,644	16,694
Preferred stock, aggregate liquidation preference	$ 1.0	$ 1.0