Treasury Stock	12 Months Ended
Dec. 31, 2015
Treasruy Stock [Abstract]
Treasury Stock [Text Block]	Treasury Stock In July 2010, our Board of Directors approved a common stock purchase plan to purchase up to $40.0 million of our common stock. This plan has no expiration date and we have $22.5 million remaining on this purchase plan. We did not purchase any of our common stock in 2015. We purchased $5.6 million of our common stock in 2014. We used the treasury stock to issue shares for stock option exercises, restricted stock grants and employee stock purchase plan stock purchases. In 2015, we withheld 17,299 shares of our common stock from employee vested restricted stock units in consideration for $1.5 million in payments for the employee's share award income tax withholding obligations. In 2015, we also withheld 823 shares of our common stock from option exercises with shares remitted back to us in lieu of $0.1 million in cash payments for the option exercises. In 2014, we withheld 4,232 shares of our common stock from employee vested restricted stock units in consideration for $0.2 million in payments for the employee's share award income tax withholding obligations. In 2014, we also withheld 4,583 shares of our common stock from option exercises with shares remitted back to us in lieu of $0.3 million in cash payments for the option exercises.

Treasury Stock

In July 2010, our Board of Directors approved a common stock purchase plan to purchase up to $40.0 million of our common stock. This plan has no expiration date and we have $22.5 million remaining on this purchase plan. We did not purchase any of our common stock in 2015. We purchased $5.6 million of our common stock in 2014. We used the treasury stock to issue shares for stock option exercises, restricted stock grants and employee stock purchase plan stock purchases.

In 2015, we withheld 17,299 shares of our common stock from employee vested restricted stock units in consideration for $1.5 million in payments for the employee's share award income tax withholding obligations. In 2015, we also withheld 823 shares of our common stock from option exercises with shares remitted back to us in lieu of $0.1 million in cash payments for the option exercises.

In 2014, we withheld 4,232 shares of our common stock from employee vested restricted stock units in consideration for $0.2 million in payments for the employee's share award income tax withholding obligations. In 2014, we also withheld 4,583 shares of our common stock from option exercises with shares remitted back to us in lieu of $0.3 million in cash payments for the option exercises.