Unconsolidated Subsidiaries Unconsolidated Subsidiaries (Schedule) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Variable Interest Entity [Line Items]
Revenues	$ 193,734us-gaap_Revenues	$ 177,413us-gaap_Revenues
Gross profit	38,189us-gaap_GrossProfit	36,171us-gaap_GrossProfit
Net income (loss)	1,027us-gaap_NetIncomeLoss	(1,524)us-gaap_NetIncomeLoss
Variable interest entity, not primary beneficiary
Variable Interest Entity [Line Items]
Revenues	148,071	138,523
Gross profit	18,878	19,493
Income before income taxes	13,119	13,168
Net income (loss)	$ 10,155	$ 10,146

Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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