Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
VIE for Rail	$ 8,446.4	$ 8,204.0
VIE depreciation allowance	2,641.7	2,505.6
VIE nonrecourse debt	$ 0.0	$ 6.9
Common stock, par value	$ 0.625	$ 0.625
Common stock, shares authorized	120,000,000	120,000,000
Common stock, shares issued	66,953,606	66,776,290
Common stock, shares outstanding	39,442,893.000000	41,970,098
Treasury stock, shares outstanding	27,510,713	24,806,192

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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