Consolidated Balance Sheets (Parentheticals) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Allowance for doubtful accounts (in Dollars)	$ 1,667	$ 730
VIE assets (in Dollars)	0	6,800
VIE liabilities (in Dollars)	$ 0	$ 3,100
Common stock, par value (in Dollars per share)	$ 0	$ 0
Common stock, shares authorized	100,000,000us-gaap_CommonStockSharesAuthorized	100,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	57,326,180us-gaap_CommonStockSharesIssued	57,010,878us-gaap_CommonStockSharesIssued
Treasury stock, shares	4,814,716us-gaap_TreasuryStockShares	4,768,925us-gaap_TreasuryStockShares
Common Class A [Member]
Common stock, par value (in Dollars per share)	$ 0	$ 0
Common stock, shares authorized	15,000,000	15,000,000
Common stock, shares issued	7,567,868	7,331,574
Treasury stock, shares	1,578,554	1,578,554

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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