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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Self-Insurance Liabilities and Related Costs (Detail) - USD ($)
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Capital Leased Assets [Line Items]    
Maximum exposure automobile plan per individual event $ 1,000  
Self insurance reserves 14,480,000 $ 13,707,000
Automobile Plan    
Capital Leased Assets [Line Items]    
Maximum exposure automobile plan per individual event $ 1,200