Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Operating Activities
Net income	$ 95,702	$ 75,565	$ 96,825
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization	55,307	48,977	40,837
Bad debt expense	1,187	1,129	187
Cash distributions (less than) in excess of income of unconsolidated affiliates	(50,953)	8,134	(23,591)
Gains on sales of railcars and related leases	(19,366)	(23,665)	(8,417)
Excess tax benefit from share-based payment arrangement	(1,001)	(162)	(307)
Deferred income taxes	40,374	16,503	5,473
Stock based compensation expense	4,339	3,990	4,071
Lower of cost or market inventory and contract adjustment	0	262	3,142
Impairment of property, plant and equipment	4,439	531	1,704
Other	498	(672)	254
Changes in operating assets and liabilities:
Accounts receivable	35,446	(21,737)	(15,708)
Inventories	162,443	122,428	(114,427)
Commodity derivatives	69,633	2,947	134,309
Other assets	(4,926)	(12,927)	(1,104)
Accounts payable for grain	9,530	101,265	117,309
Other accounts payable and accrued expenses	(65,464)	5,914	49,708
Net cash provided by operating activities	337,188	328,482	290,265
Investing Activities
Purchase of investments	0	(19,996)	0
Proceeds from redemption of investment	0	19,998	0
Acquisition of businesses, net of cash acquired	(15,252)	(220,257)	(2,365)
Purchases of railcars	(92,584)	(111,224)	(64,161)
Proceeds from sale of railcars	97,232	90,827	30,398
Purchases of property, plant and equipment	(46,786)	(69,274)	(44,162)
Proceeds from sale of property, plant and equipment	390	1,116	931
Investments in affiliates	(49,251)	0	(121)
Change in restricted cash	(10)	18,253	(6,517)
Net cash used in investing activities	(106,261)	(290,557)	(85,997)
Financing Activities
Net change in short-term borrowings	(24,219)	(47,281)	(169,600)
Proceeds from issuance of long-term debt	68,003	275,346	73,752
Payments of long-term debt	(94,752)	(143,943)	(104,008)
Proceeds from minority investor	0	6,100	0
Proceeds from sale of treasury shares to employees and directors	1,939	1,322	815
Payments of debt issuance costs	(46)	(637)	(3,170)
Purchase of treasury stock	0	0	(3,040)
Dividends paid	(11,986)	(11,166)	(8,153)
Excess tax benefit from share-based payment arrangement	1,001	162	307
Net cash provided by (used in) financing activities	(60,060)	79,903	(213,097)
Increase (decrease) in cash and cash equivalents	170,867	117,828	(8,829)
Cash and cash equivalents at beginning of year	138,218	20,390	29,219
Cash and cash equivalents at end of year	309,085	138,218	20,390
Supplemental disclosure of cash flow information
Capital projects incurred but not yet paid	3,870	2,876	0
Purchase of a productive asset through seller-financing	14,694	10,498	0
Outstanding payment for acquisition of business	$ 128	$ 3,345	$ 0