Condensed Consolidated Statements of Operations (Unaudited) (USD $) In Thousands, except Per Share data	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Condensed Consolidated Statements of Operations [Abstract]
Net sales	$ 282,568	$ 240,132	$ 555,356	$ 463,128
Costs and expenses:
Cost of materials (exclusive of depreciation and amortization)	208,470	178,515	409,898	347,558
Warehouse, processing and delivery expense	33,874	30,176	67,016	59,080
Sales, general, and administrative expense	30,864	25,808	61,985	52,750
Depreciation and amortization expense	5,059	5,351	10,058	10,501
Operating income (loss)	4,301	282	6,399	(6,761)
Interest expense, net	(1,120)	(1,252)	(2,106)	(2,545)
Income (loss) before income taxes and equity in earnings of joint venture	3,181	(970)	4,293	(9,306)
Income taxes	(2,466)	(70)	(3,734)	2,778
Income (loss) before equity in earnings of joint venture	715	(1,040)	559	(6,528)
Equity in earnings of joint venture	2,982	1,448	5,841	2,314
Net income (loss)	$ 3,697	$ 408	$ 6,400	$ (4,214)
Basic income (loss) per share	$ 0.16	$ 0.02	$ 0.28	$ (0.18)
Diluted income (loss) per share	$ 0.16	$ 0.02	$ 0.28	$ (0.18)
Dividends per common share	$ 0.00	$ 0.00	$ 0.00	$ 0.00

Sum of operating profit and nonoperating income or expense before income or loss from equity method investments, net of income taxes.

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Operating costs associated with the warehousing, processing and delivery of goods during the period. These costs include occupancy costs, compensation and employee benefits for warehouse personnel, processing and shipping and handling costs.

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Aggregate dividends paid during the period for each share of common stock outstanding.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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The amount of net income or loss for the period per each share of common stock outstanding during the reporting period.

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The amount of net income or loss for the period per each share of common stock and dilutive common stock equivalents outstanding during the reporting period.

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. Such amount typically reflects adjustments similar to those made in preparing consolidated statements, including adjustments to eliminate intercompany gains and losses, and to amortize, if appropriate, any difference between cost and underlying equity in net assets of the investee at the date of investment.

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The sum of the current income tax expense (benefit) and the deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of net interest income or expense derived from banking operations.

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The portion of consolidated profit or loss for the period, net of income taxes, which is attributable to the parent. If the entity does not present consolidated financial statements, the amount of profit or loss for the period, net of income taxes.

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The net result for the period of deducting operating expenses from operating revenues.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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