Consolidated Statements of Cash Flows (Unaudited) (USD $) In Millions, unless otherwise specified	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011
Operating activities:
Net income	$ 119.8	$ 57.2
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	98.7	95.4
Stock-based compensation expense	12.5	9.4
Excess tax benefits from stock-based compensation	(1.2)	(0.3)
Provision for deferred income taxes	61.9	16.6
Net gains on sales of railcars owned more than one year at the time of sale	(5.3)	(1.5)
Gain on disposition of property, plant, equipment, and other assets	(6.1)	(3.9)
Other	5.5	6.6
Changes in assets and liabilities:
(Increase) decrease in receivables	49.4	(99.2)
(Increase) decrease in income tax receivable	(3.6)	3.0
(Increase) decrease in inventories	(100.0)	(138.4)
(Increase) decrease in other assets	(26.0)	(4.9)
Increase (decrease) in accounts payable	27.2	57.2
Increase (decrease) in accrued liabilities	(29.4)	(5.4)
Increase (decrease) in other liabilities	(4.9)	17.0
Net cash provided by operating activities	198.5	8.8
Investing activities:
(Increase) decrease in short-term marketable securities		116.0
Proceeds from sales of railcars owned more than one year at the time of sale	34.1	12.2
Proceeds from lease fleet sales - sale and leaseback	7.2
Proceeds from disposition of property, plant, equipment, and other assets	13.3	5.3
Capital expenditures - leasing, net of sold railcars owned one year or less	(172.5)	(151.9)
Capital expenditures - manufacturing and other	(36.8)	(24.6)
Acquisitions, net of cash acquired	0	(15.3)
Net cash required by investing activities	(154.7)	(58.3)
Financing activities:
Proceeds from issuance of common stock, net	1.4	1.6
Excess tax benefits from stock-based compensation	1.2	0.3
Payments to retire debt - other	(86.7)	(79.1)
Proceeds from issuance of debt	16.2	52.7
Deferred loan issuance costs		(5.9)
(Increase) decrease in restricted cash	21.4	1.8
Shares repurchased	(35.2)
Dividends paid to common shareholders	(14.5)	(12.7)
Other	(4.6)	(6.1)
Net cash required by financing activities	(100.8)	(47.4)
Net decrease in cash and cash equivalents	(57.0)	(96.9)
Cash and cash equivalents at beginning of period	351.1	354.0
Cash and cash equivalents at end of period	$ 294.1	$ 257.1

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).