GOODWILL AND OTHER INTANGIBLE ASSETS - Carrying Values of Other Intangible Assets (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Intangible Assets By Major Class [Line Items]
Gross Carrying Amount	$ 2,171,857	$ 2,133,541
Accumulated Amortization	332,423	271,568
Net Value	1,839,434	1,861,973	$ 1,842,561
Operating permits
Intangible Assets By Major Class [Line Items]
Carrying Amount, Indefinite Lived Intangible Assets	230,449	229,396
Tradenames
Intangible Assets By Major Class [Line Items]
Carrying Amount, Indefinite Lived Intangible Assets	320,284	316,472
Customer relationships
Intangible Assets By Major Class [Line Items]
Gross Carrying Amount	1,588,761	1,553,398
Accumulated Amortization	322,378	261,306
Net Value	1,266,383	1,292,092
Covenants not-to-compete
Intangible Assets By Major Class [Line Items]
Gross Carrying Amount	7,888	9,491
Accumulated Amortization	5,378	6,371
Net Value	2,510	3,120
Tradenames
Intangible Assets By Major Class [Line Items]
Gross Carrying Amount	5,872	5,708
Accumulated Amortization	1,595	1,365
Net Value	4,277	4,343
Other
Intangible Assets By Major Class [Line Items]
Gross Carrying Amount	18,603	19,076
Accumulated Amortization	3,072	2,526
Net Value	$ 15,531	$ 16,550