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BUSINESS COMBINATIONS - Schedule of Unaudited Pro forma Combined Information (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Business Combinations [Abstract]
Revenues									$ 773,845	$ 752,916	$ 708,909
Operating income (loss)									56,997	49,893	(1,061)
Net income (loss)									$ 33,893	$ 12,167	$ (15,291)
Basic weighted average shares outstanding	47,811	47,690	47,464	45,913	42,936	42,779	42,661	42,370	47,226	42,688	41,846
Basic earnings (loss) per common share (in dollars per share)									$ 0.72	$ 0.29	$ (0.37)
Diluted weighted average shares outstanding	48,583	48,361	48,221	42,913	42,936	44,175	43,916	42,370	47,966	44,168	41,846
Diluted earnings (loss) per common share (in dollars per share)									$ 0.71	$ 0.28	$ (0.37)

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The pro forma operating income for the period as if the business combination or combinations had been completed at the beginning of the period.

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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