Stock Plans	6 Months Ended
Jun. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock Plans	9. STOCK PLANS: During the six months ended June 30, 2018, the Company granted 0.1 million restricted stock units with a weighted-average grant date fair value of $71.34 per award. There were 0.4 million restricted stock units outstanding at June 30, 2018 and December 31, 2017. The compensation expense that has been charged against pre-tax income for all of the Company’s stock-based compensation plans was $2.0 million and $1.6 million for the three months ended June 30, 2018 and 2017, respectively, and $3.9 million and $3.2 million for the six months ended June 30, 2018 and 2017, respectively.

Stock Plans

6 Months Ended

Jun. 30, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

9. STOCK PLANS:

During the six months ended June 30, 2018, the Company granted 0.1 million restricted stock units with a weighted-average grant date fair value of $71.34 per award. There were 0.4 million restricted stock units outstanding at June 30, 2018 and December 31, 2017.

The compensation expense that has been charged against pre-tax income for all of the Company’s stock-based compensation plans was $2.0 million and $1.6 million for the three months ended June 30, 2018 and 2017, respectively, and $3.9 million and $3.2 million for the six months ended June 30, 2018 and 2017, respectively.