Condensed Consolidated Balance Sheets [Parenthetical] (USD $)	Mar. 31, 2015	Dec. 31, 2014
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized	10,000,000us-gaap_PreferredStockSharesAuthorized	10,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, shares issued	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Preferred stock, shares outstanding	0us-gaap_PreferredStockSharesOutstanding	0us-gaap_PreferredStockSharesOutstanding
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized	150,000,000us-gaap_CommonStockSharesAuthorized	150,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	47,471,904us-gaap_CommonStockSharesIssued	44,974,248us-gaap_CommonStockSharesIssued
Common stock, shares outstanding	47,430,595us-gaap_CommonStockSharesOutstanding	44,932,939us-gaap_CommonStockSharesOutstanding
Treasury stock, shares	41,309us-gaap_TreasuryStockShares	41,309us-gaap_TreasuryStockShares

Face amount or stated value per share of common stock.

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