SHARE-BASED COMPENSATION (Tables)

12 Months Ended

Dec. 31, 2017

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

Summary of Transactions Involving Stock Units and Director Stock Grants

Transactions involving our stock units and director stock grants are summarized below:

	Twelve Months Ended December 31, 2017				Twelve Months Ended December 31, 2016
	No. of Stock Units		Weighted  Average Fair Value		No. of Stock Units		Weighted  Average Fair Value
	(in thousands)				(in thousands)
Stock and stock units, beginning of year	535		$	35.11	371		$	36.26
Changes during the year:
Granted	563		$	13.64	322		$	34.23
Assumed - Furmanite Acquisition	—		$	—	40		$	25.63
Vested and settled	(211	)	$	34.10	(180	)	$	34.19
Cancelled	(33	)	$	30.12	(18	)	$	30.75
Stock and stock units, end of year	854		$	21.42	535		$	35.11

	Seven Months Ended December 31, 2015				Twelve Months Ended May 31, 2015
	No. of Stock Units		Weighted  Average Fair Value		No. of Stock Units		Weighted  Average Fair Value
	(in thousands)				(in thousands)
Stock and stock units, beginning of year	304		$	36.23	310		$	31.42
Changes during the year:
Granted	197		$	35.14	156		$	39.51
Vested and settled	(126	)	$	34.43	(133	)	$	29.23
Cancelled	(4	)	$	39.27	(29	)	$	34.12
Stock and stock units, end of year	371		$	36.26	304		$	36.23

Summary of Transactions Involving Performance Awards

Transactions involving our performance awards are summarized below:

	Twelve Months Ended December 31, 2016				Seven Months Ended December 31, 2015
	No. of Performance Awards		Weighted Average Fair Value		No. of Performance Awards		Weighted Average Fair Value
	(in thousands)				(in thousands)
Performance awards, beginning of year	13		$	35.15	28		$	32.86
Changes during the year:
Granted	—		$	—	—		$	—
Vested and settled	(13	)	$	35.15	(15	)	$	30.82
Cancelled	—		$	—	—		$	—
Performance awards, end of year	—		$	35.15	13		$	35.15

	Twelve Months Ended May 31, 2015
	No. of Performance Awards		Weighted Average Fair Value
	(in thousands)
Performance awards, beginning of year	50		$	30.63
Changes during the year:
Granted	—		$	—
Vested and settled	(22	)	$	27.66
Cancelled	—		$	—
Performance awards, end of year	28		$	32.86

Transactions involving our performance awards are summarized below:

	Twelve Months Ended December 31, 2017				Twelve Months Ended December 31, 2016
	No. of Long- Term Performance Stock Units		Weighted Average Fair Value		No. of Long- Term Performance Stock Units	Weighted Average Fair Value
	(in thousands)				(in thousands)
Long-term performance stock units, beginning of year	59		$	37.16	59	$	37.16
Changes during the year:
Granted	182		$	19.68	—	$	—
Vested and settled	—		$	—	—	$	—
Cancelled	(67	)	$	30.11	—	$	—
Long-term performance stock units, end of year	174		$	21.58	59	$	37.16

	Seven Months Ended December 31, 2015			Twelve Months Ended May 31, 2015
	No. of Long- Term Performance Stock Units	Weighted Average Fair Value		No. of Long- Term Performance Stock Units	Weighted Average Fair Value
	(in thousands)			(in thousands)
Long-term performance stock units, beginning of year	23	$	42.25	—	$	—
Changes during the year:
Granted	36	$	33.91	23	$	42.25
Vested and settled	—	$	—	—	$	—
Cancelled	—	$	—	—	$	—
Long-term performance stock units, end of year	59	$	37.16	23	$	42.25

Summary of Transactions Involving Stock Options

Transactions involving our stock options are summarized below:

	Twelve Months Ended December 31, 2017				Twelve Months Ended December 31, 2016
	No. of Options		Weighted Average Exercise Price		No. of Options		Weighted Average Exercise Price
	(in thousands)				(in thousands)
Shares under option, beginning of year	203		$	30.63	376		$	25.71
Changes during the year:
Granted	—		$	—	—		$	—
Assumed - Furmanite Acquisition	—		$	—	132		$	33.20
Exercised	(16	)	$	27.91	(251	)	$	23.50
Cancelled	—		$	—	(50	)	$	35.00
Expired	(108	)	$	30.08	(4	)	$	44.62
Shares under option, end of year	79		$	31.94	203		$	30.63
Exercisable at end of year	79		$	31.94	203		$	30.63

	Seven Months Ended December 31, 2015				Twelve Months Ended May 31, 2015
	No. of Options		Weighted Average Exercise Price		No. of Options		Weighted Average Exercise Price
	(in thousands)				(in thousands)
Shares under option, beginning of year	490		$	24.80	816		$	19.61
Changes during the year:
Granted	—		$	—	—		$	—
Exercised	(109	)	$	21.41	(326	)	$	11.79
Cancelled	—		$	—	—		$	—
Expired	(5	)	$	30.33	—		$	—
Shares under option, end of year	376		$	25.71	490		$	24.80
Exercisable at end of year	376		$	25.71	490		$	24.80

Total Options Outstanding, Range of Exercise Prices and Remaining Contractual Lives

Options exercisable at December 31, 2017 had a weighted-average remaining contractual life of 3.8 years. For total options outstanding at December 31, 2017, the range of exercise prices and remaining contractual lives are as follows:

Range of Prices	No. of Options	Weighted Average Exercise Price		Weighted Average Remaining Life
	(in thousands)			(in years)
$20.19 to $30.28	14	$	21.68	3.3
$30.29 to $40.38	58	$	32.07	3.6
$40.39 to $50.47	7	$	50.47	6.4
	79	$	31.94	3.8