STOCK-BASED COMPENSATION (Tables)

12 Months Ended

Dec. 31, 2020

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Restricted Stock and Units Activity

The following table summarizes the activity related to restricted stock unit (RSU) share based payment awards:

	Number of Shares			Weighted- Average Grant-Date Fair Value
Unvested, January 1, 2020		98,810		$	144.53
Granted		143,179			162.32
Vested		(47,750	)		136.59
Forfeited		(1,615	)		122.83
Unvested, December 31, 2020		192,624		$	160.99

The following table summarizes the activity related to restricted stock award (RSA) share based payment awards:

	Number of Shares			Weighted- Average Grant-Date Fair Value
Unvested, January 1, 2020		311,643		$	80.94
Granted		1,926			155.85
Vested		(171,908	)		50.65
Unvested, December 31, 2020		141,661		$	124.81

Schedule of Nonvested Performance-Based Units Activity

The following table summarizes the activity related to performance unit awards (PSU) share based payment awards:

	Number of Shares			Weighted- Average Grant-Date Fair Value
Unvested, January 1, 2020		37,781		$	134.97
Granted		111,410			167.74
Vested		(31,276	)		105.65
Unvested, December 31, 2020		117,915		$	165.48