CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Accounts receivable, allowance	$ 13,760	$ 11,555
Treasury stock - Common stock, Shares	82,535us-gaap_TreasuryStockShares	75,676us-gaap_TreasuryStockShares
Common stock
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, Authorized	1,600,000	1,600,000
Common stock, Shares issued	196,802	192,562
Common stock, Shares outstanding	114,267	116,886
Class B Common Stock
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, Authorized	400,000	400,000
Common stock, Shares issued	12,800	12,800
Common stock, Shares outstanding	12,800	12,800

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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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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