SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES AND PRACTICES - Additional Information (Detail)				3 Months Ended		7 Months Ended	12 Months Ended
	Jan. 01, 2018 USD ($)	Dec. 01, 2017 USD ($)	Aug. 31, 2015 USD ($) shares	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Dec. 31, 2015 USD ($) shares	Dec. 31, 2017 USD ($) employee country segment Location customer	Dec. 31, 2016 USD ($)	May 31, 2015 USD ($) shares	Jan. 01, 2017 USD ($)	Dec. 01, 2016 USD ($)	Jul. 07, 2015 USD ($)	May 31, 2014 USD ($)
Significant Accounting Policies [Line Items]
Number of operating segments | segment							3
Number of locations in which company operates | Location							220
Number of countries in which company operates | country							20
Number of employees | employee							7,300
Unbilled revenues							$ 69,138,000	$ 39,719,000
Goodwill impairment loss		$ 0		$ 75,200,000	$ 0	$ 0	75,241,000	$ 0	$ 0
Discounted cash flow, forecast period								5 years
Goodwill impairment test, number of market-based approaches								2
Amount of Market Capitalization in Excess of Carrying Amount					$ 175,000,000						$ 437,000,000
Percentage of Market Capitalization in Excess of Carrying Amount					33.00%						80.00%
Percentage change in stock price				43.00%
Goodwill						256,654,000	284,804,000	$ 355,786,000
Accumulated goodwill impairment loss								0
Deferred tax assets, gross							59,652,000	67,707,000
Valuation allowance							26,185,000	13,168,000
Deferred tax liabilities							33,309,000	70,587,000
Unrecognized tax benefits						$ 539,000	$ 1,159,000	858,000	$ 477,000				$ 715,000
US Federal income tax rate	21.00%						35.00%
Workers compensation our self-insured retention							$ 1,000,000
Automobile liability self-insured retention							500,000
General liability claims we have an effective self-insured retention							3,000,000
Medical claims, our self-insured retention							350,000
Environmental liability claims, our self-insured retention							1,000,000
Share-based awards outstanding excluded from calculation of diluted EPS | shares						0			0
Cash payment to acquire non-controlling interest						$ 5,934,000	0	0	$ 0
Income tax deficiency from share-based compensation arrangements recognized in statement of operations							1,800,000
Quest Integrity
Significant Accounting Policies [Line Items]
Number of shares issued to acquire noncontrolling interest | shares			728,266
Cash payment to acquire non-controlling interest			$ 5,900,000
Qualspec Group
Significant Accounting Policies [Line Items]
Goodwill												$ 148,482,000
TeamFurmanite
Significant Accounting Policies [Line Items]
Goodwill impairment loss							54,101,000	0
Reporting unit, percentage of fair value in excess of carrying amount					46.00%
Goodwill						19,874,000	56,600,000	109,059,000
TeamQualspec
Significant Accounting Policies [Line Items]
Goodwill impairment loss							21,140,000	0
Reporting unit, percentage of fair value in excess of carrying amount					65.00%
Goodwill						$ 207,497,000	194,211,000	$ 213,475,000
TeamQualspec | Qualspec Group
Significant Accounting Policies [Line Items]
Goodwill												$ 148,500,000
Significant Other Observable Inputs (Level 2) | Convertible Debt
Significant Accounting Policies [Line Items]
Fair value of convertible senior notes							$ 231,600,000
Sales Revenue | Customer Concentration Risk
Significant Accounting Policies [Line Items]
Number of customers that accounted for more than ten percent of revenue | customer							0
Accounting Standards Update 2016-09
Significant Accounting Policies [Line Items]
Adjustment to opening retained earnings upon adoption										$ 1,000,000
Maximum | Forecasted | Accounting Standards Update 2014-09
Significant Accounting Policies [Line Items]
Adjustment to opening retained earnings upon adoption	$ 10,000,000
Research and development tax credit
Significant Accounting Policies [Line Items]
Tax credit carryforward							$ 800,000
Foreign Subsidiaries
Significant Accounting Policies [Line Items]
Net operating loss carryforwards, not expected to be realized							6,000,000
Domestic Tax Authority
Significant Accounting Policies [Line Items]
Net operating loss carryforwards, not expected to be realized							$ 99,000,000