Treasury Stock	3 Months Ended
Mar. 31, 2016
Treasury 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. During the first quarter of 2016 we purchased 174,885 shares of our common stock for $15.4 million, including commissions. As of March 31, 2016, we had $7.2 million remaining on this purchase plan. We expect to use the treasury stock to issue shares for stock option exercises, restricted stock grants and employee stock purchase plan stock purchases. Additionally, in the first three months of 2016, we withheld 17,528 shares of our common stock from employee vested restricted stock units in consideration for $1.5 million in payments made on the employee's behalf for their minimum statutory income tax withholding obligations.

Treasury Stock

3 Months Ended

Mar. 31, 2016

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. During the first quarter of 2016 we purchased 174,885 shares of our common stock for $15.4 million, including commissions. As of March 31, 2016, we had $7.2 million remaining on this purchase plan. We expect to use the treasury stock to issue shares for stock option exercises, restricted stock grants and employee stock purchase plan stock purchases.

Additionally, in the first three months of 2016, we withheld 17,528 shares of our common stock from employee vested restricted stock units in consideration for $1.5 million in payments made on the employee's behalf for their minimum statutory income tax withholding obligations.