Note 10 - Stockholders' Equity	12 Months Ended
Dec. 31, 2019
Notes to Financial Statements
Stockholders' Equity Note Disclosure [Text Block]	10. STOCKHOLDERS’ EQUITY Share Repurchase Plan In December 2018, the Company’s board of directors authorized the open market repurchase of up to two million shares of the Company’s common stock through one or more trading plans established in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934. The program did not establish a time period in which the repurchases had to be made. In December 2018, the Company amended its Credit Facility, which limited the open market share repurchases to $32.0 million for 2019. The Company began repurchasing shares under this program in January 2019. In December 2019, the Company’s board of directors authorized the open market repurchase of up to an additional two million shares of the Company’s common stock. The program did not establish a time period in which the repurchases had to be made, although the authorization is limited to $40.0 million in 2020 by the Company’s amended Credit Facility while the Company’s consolidated financial leverage ratio remains greater than 2.50 to 1.00. Once repurchased, the Company promptly retires such shares. The Company is also authorized to repurchase up to $10.0 million of the Company’s common stock in each calendar year in connection with the Company’s equity compensation programs for employees. The participants in the Company’s equity plans may surrender shares of common stock in satisfaction of tax obligations arising from the vesting of restricted stock and restricted stock unit awards under such plans and in connection with the exercise of stock option awards. The deemed price paid is the closing price of the Company’s common stock on The Nasdaq Global Select Market on the date that the restricted stock or restricted stock unit vests or the shares of the Company’s common stock are surrendered in exchange for stock option exercises. With regard to stock option awards, the option holder may elect a “net, net” exercise in connection with the exercise of employee stock options such that the option holder receives a number of shares equal to the built-in gain in the option shares divided by the market price of the Company’s common stock on the date of exercise, less a number of shares equal to the taxes due upon the exercise of the option divided by the market price of the Company’s common stock on the date of exercise. The shares of Company common stock surrendered to the Company for taxes due on the exercise of the option are deemed repurchased by the Company. During 2019, the Company acquired 1,492,348 shares of the Company’s common stock for $26.3 million ($17.64 average price per share) through the open market repurchase program discussed above, 151,234 shares of the Company’s common stock for $3.1 million ($20.26 average price per share) in connection with the satisfaction of tax obligations in connection with the vesting of restricted stock units and performance units, and 48,409 shares of the Company’s common stock for $1.0 million ($20.52 average price per share) in connection with “net, net” exercises of employee stock options. Once repurchased, the Company immediately retired all such shares. During 2018, the Company acquired 949,464 shares of the Company’s common stock for $20.3 million ($21.36 average price per share) through the open market repurchase programs discussed above and 228,068 shares of the Company’s common stock for $5.5 million ($24.08 average price per share) in connection with the satisfaction of tax obligations in connection with the vesting of restricted stock and restricted stock units. Once repurchased, the Company immediately retired all such shares. During 2018, the Company did not acquire any of the Company’s common stock in connection with “net, net” exercises of employee stock options. During 2017, the Company acquired 1,599,093 shares of the Company’s common stock for $35.3 million ($22.10 average price per share) through open market repurchase programs and 112,899 shares of the Company’s common stock for $2.5 million ($22.15 average price per share) in connection with the satisfaction of tax obligations in connection with the vesting of restricted stock and restricted stock units. Once repurchased, the Company immediately retired all such shares. During 2017, the Company did not acquire any of the Company’s common stock in connection with “net, net” exercises of employee stock options. Equity-Based Compensation Plans Employee Plans In April 2016, the Company’s stockholders approved the 2016 Employee Equity Incentive Plan, which was amended in 2017 by the First Amendment to the 2016 Employee Equity Incentive Plan (as amended, the “2016 Employee Plan”). In April 2018, the Company’s stockholders approved the Second Amendment to the 2016 Employee Equity Incentive Plan, which increased by 1,700,000 the number of shares of the Company’s common stock reserved and available for issuance in connection with awards issued under the 2016 Employee Plan. The 2016 Employee Plan, which replaced the 2013 Employee Equity Incentive Plan, provides for equity-based compensation awards, including restricted shares of common stock, performance awards, stock options, stock units and stock appreciation rights. The 2016 Employee Plan is administered by the compensation committee of the board of directors, which determines eligibility, timing, pricing, amount and other terms or conditions of awards. As of December 31, 2019, 2,099,380 shares of the Company’s common stock were available for issuance under the 2016 Employee Plan. Director Plans In April 2016, the Company’s stockholders approved the 2016 Non-Employee Director Equity Incentive Plan (the “2016 Director Plan”), which replaced the 2011 Non-Employee Director Equity Incentive Plan. In April 2019, the Company’s stockholders approved an amendment and restatement of the 2016 Director Plan, which among other things, increased by 300,000 the number of shares of the Company’s common stock reserved and available for issuance in connection with awards issued under the 2016 Director Plan. The 2016 Director Plan provides for equity-based compensation awards, including non-qualified stock options and stock units. The board of directors administers the 2016 Director Plan and has the authority to establish, amend and rescind any rules and regulations related to the 2016 Director Plan. As of December 31, 2019, 321,406 shares of the Company’s common stock were available for issuance under the 2016 Director Plan. Prior to the 2016 Director Plan, the board of directors administered the 2011 Non-Employee Director Equity Plan (“2011 Director Plan”), the 2006 Non-Employee Director Equity Plan (“2006 Director Plan”) and the 2001 Non-Employee Director Equity Plan (“2001 Director Plan”), all of which contained substantially the same provisions as the current plan. At December 31, 2019, there were 52,296 deferred stock units outstanding under the 2011 Director Plan, 39,109 deferred stock units outstanding under the 2006 Director Plan and 31,850 deferred stock units outstanding under the 2001 Director Equity Plan. Activity and related expense associated with these plans are described in Note 11.

In December 2018, the Company’s board of directors authorized the open market repurchase of up to two million shares of the Company’s common stock through one or more trading plans established in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934. The program did not establish a time period in which the repurchases had to be made. In December 2018, the Company amended its Credit Facility, which limited the open market share repurchases to $32.0 million for 2019. The Company began repurchasing shares under this program in January 2019. In December 2019, the Company’s board of directors authorized the open market repurchase of up to an additional two million shares of the Company’s common stock. The program did not establish a time period in which the repurchases had to be made, although the authorization is limited to $40.0 million in 2020 by the Company’s amended Credit Facility while the Company’s consolidated financial leverage ratio remains greater than 2.50 to 1.00. Once repurchased, the Company promptly retires such shares.

The Company is also authorized to repurchase up to $10.0 million of the Company’s common stock in each calendar year in connection with the Company’s equity compensation programs for employees. The participants in the Company’s equity plans may surrender shares of common stock in satisfaction of tax obligations arising from the vesting of restricted stock and restricted stock unit awards under such plans and in connection with the exercise of stock option awards. The deemed price paid is the closing price of the Company’s common stock on The Nasdaq Global Select Market on the date that the restricted stock or restricted stock unit vests or the shares of the Company’s common stock are surrendered in exchange for stock option exercises. With regard to stock option awards, the option holder may elect a “net, net” exercise in connection with the exercise of employee stock options such that the option holder receives a number of shares equal to the built-in gain in the option shares divided by the market price of the Company’s common stock on the date of exercise, less a number of shares equal to the taxes due upon the exercise of the option divided by the market price of the Company’s common stock on the date of exercise. The shares of Company common stock surrendered to the Company for taxes due on the exercise of the option are deemed repurchased by the Company.

During 2019, the Company acquired 1,492,348 shares of the Company’s common stock for $26.3 million ($17.64 average price per share) through the open market repurchase program discussed above, 151,234 shares of the Company’s common stock for $3.1 million ($20.26 average price per share) in connection with the satisfaction of tax obligations in connection with the vesting of restricted stock units and performance units, and 48,409 shares of the Company’s common stock for $1.0 million ($20.52 average price per share) in connection with “net, net” exercises of employee stock options. Once repurchased, the Company immediately retired all such shares.

During 2018, the Company acquired 949,464 shares of the Company’s common stock for $20.3 million ($21.36 average price per share) through the open market repurchase programs discussed above and 228,068 shares of the Company’s common stock for $5.5 million ($24.08 average price per share) in connection with the satisfaction of tax obligations in connection with the vesting of restricted stock and restricted stock units. Once repurchased, the Company immediately retired all such shares. During 2018, the Company did not acquire any of the Company’s common stock in connection with “net, net” exercises of employee stock options.

During 2017, the Company acquired 1,599,093 shares of the Company’s common stock for $35.3 million ($22.10 average price per share) through open market repurchase programs and 112,899 shares of the Company’s common stock for $2.5 million ($22.15 average price per share) in connection with the satisfaction of tax obligations in connection with the vesting of restricted stock and restricted stock units. Once repurchased, the Company immediately retired all such shares. During 2017, the Company did not acquire any of the Company’s common stock in connection with “net, net” exercises of employee stock options.

Equity-Based Compensation Plans

Employee Plans

In April 2016, the Company’s stockholders approved the 2016 Employee Equity Incentive Plan, which was amended in 2017 by the First Amendment to the 2016 Employee Equity Incentive Plan (as amended, the “2016 Employee Plan”). In April 2018, the Company’s stockholders approved the Second Amendment to the 2016 Employee Equity Incentive Plan, which increased by 1,700,000 the number of shares of the Company’s common stock reserved and available for issuance in connection with awards issued under the 2016 Employee Plan. The 2016 Employee Plan, which replaced the 2013 Employee Equity Incentive Plan, provides for equity-based compensation awards, including restricted shares of common stock, performance awards, stock options, stock units and stock appreciation rights. The 2016 Employee Plan is administered by the compensation committee of the board of directors, which determines eligibility, timing, pricing, amount and other terms or conditions of awards. As of December 31, 2019, 2,099,380 shares of the Company’s common stock were available for issuance under the 2016 Employee Plan.

Director Plans

In April 2016, the Company’s stockholders approved the 2016 Non-Employee Director Equity Incentive Plan (the “2016 Director Plan”), which replaced the 2011 Non-Employee Director Equity Incentive Plan. In April 2019, the Company’s stockholders approved an amendment and restatement of the 2016 Director Plan, which among other things, increased by 300,000 the number of shares of the Company’s common stock reserved and available for issuance in connection with awards issued under the 2016 Director Plan. The 2016 Director Plan provides for equity-based compensation awards, including non-qualified stock options and stock units. The board of directors administers the 2016 Director Plan and has the authority to establish, amend and rescind any rules and regulations related to the 2016 Director Plan. As of December 31, 2019, 321,406 shares of the Company’s common stock were available for issuance under the 2016 Director Plan.

Prior to the 2016 Director Plan, the board of directors administered the 2011 Non-Employee Director Equity Plan (“2011 Director Plan”), the 2006 Non-Employee Director Equity Plan (“2006 Director Plan”) and the 2001 Non-Employee Director Equity Plan (“2001 Director Plan”), all of which contained substantially the same provisions as the current plan. At December 31, 2019, there were 52,296 deferred stock units outstanding under the 2011 Director Plan, 39,109 deferred stock units outstanding under the 2006 Director Plan and 31,850 deferred stock units outstanding under the 2001 Director Equity Plan.

Activity and related expense associated with these plans are described in Note 11.