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Stockholders' Equity	3 Months Ended
Stockholders' Equity	Mar. 31, 2018
Equity [Abstract]
Stockholders' Equity	Stockholders' Equity We received 28,039 and 81,280 shares of common stock that were surrendered in payment for the exercise of stock options during the three months ended March 31, 2018 and 2017, respectively.