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 earnings	$ 86,896	$ 63,823	$ 4,336
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation	27,712	23,850	22,167
Amortization of deferred costs	633	605	699
Loss on disposal of property, plant and equipment	24	37	171
Change in interest receivable, due from affiliates	0	292	(105)
Loss from joint ventures	8,595	451	7,900
Provision for deferred income taxes	39,707	37,113	6,533
Adjustment to provision for losses on accounts receivable	48	90	(22)
Item related to investing activities:
Realized and unrealized gain on short-term investments—available for sale securities	(141)	(3,730)	0
Item related to financing activities:
Loss on debt extinguishment	392	2,267	0
Changes in operating assets and liabilities:
Accounts receivable, net	14,077	(2,568)	(12,616)
Accounts receivable, due from affiliates	(12,904)	2,588	(1,170)
Income taxes receivable	(2,316)	4,057	10,590
Inventories, net	19,819	(14,224)	(45,813)
Prepaid expenses and other current assets	(398)	621	(1,885)
Accounts payable	(12,184)	2,653	32,988
Accounts payable, due to affiliates	(1,421)	2,031	525
Accrued expenses and taxes	5,468	3,633	4,183
Other	(9,241)	(2,211)	(358)
Net cash provided by operating activities	164,766	121,378	28,123
Investing activities:
Purchases of property, plant and equipment	(22,025)	(19,962)	(6,202)
Capital expenditures—leased railcars	(162,068)	(185,918)	(29,444)
Proceeds from sale of property, plant and equipment	54	259	122
Purchase of short-term investments—available for sale securities	0	(40,334)	0
Proceeds from sale of short-term investments—available for sale securities	12,699	31,506	0
Proceeds from repayments of loans by joint ventures and sale of investment in joint venture	5,100	1,908	775
Investments in and loans to joint ventures	(136)	(1,856)	(5,711)
Net cash used in investing activities	(166,376)	(214,397)	(40,460)
Financing activities:
Repayment of long-term debt	(180,083)	(100,000)	0
Proceeds from long-term debt	99,841	100,000	0
Restricted cash	(3,908)	0	0
Premium paid on debt redemption	0	(1,875)	0
Payment of common stock dividends	(21,352)	(5,338)	0
Debt issuance costs	(543)	(1,917)	0
Proceeds from stock option exercises	0	0	756
Net cash (used in) provided by financing activities	(106,045)	(9,130)	756
Effect of exchange rate changes on cash and cash equivalents	(138)	22	(5)
Decrease in cash and cash equivalents	(107,793)	(102,127)	(11,586)
Cash and cash equivalents at beginning of year	205,045	307,172	318,758
Cash and cash equivalents at end of year	$ 97,252	$ 205,045	$ 307,172