Condensed Consolidating Statements of Income (Detail) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended 12 Months Ended
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2017
Jun. 30, 2016
Dec. 31, 2016
Revenues:          
Rental $ 117,851 $ 116,773 $ 232,593 $ 234,129  
Sales 8,401 6,342 16,379 13,233  
Other 438 1,734 1,245 2,020  
Total revenues 126,690 124,849 250,217 249,382  
Costs and expenses:          
Rental, selling and general expenses 82,850 78,037 161,209 154,339  
Cost of sales 5,408 3,678 10,520 8,289  
Restructuring expenses 538 1,324 1,437 3,572 $ 6,020
Depreciation and amortization 15,742 16,269 31,006 31,446  
Total costs and expenses 104,538 99,308 204,172 197,646  
Income from operations 22,152 25,541 46,045 51,736  
Other income (expense):          
Interest income 16   16    
Interest expense (8,807) (8,002) (17,209) (16,486)  
Debt extinguishment expense   (9,192)   (9,192)  
Deferred financing costs write-off   (2,271)   (2,271)  
Foreign currency exchange (18) (4) (27) (4)  
Income before income tax provision 13,343 6,072 28,825 23,783  
Income tax provision 4,566 2,000 9,896 8,713  
Net income 8,777 4,072 18,929 15,070  
Eliminations          
Other income (expense):          
Interest income (2,650) (2,653) (5,300) (5,307)  
Interest expense 2,650 2,653 5,300 5,307  
Guarantors          
Revenues:          
Rental 98,215 95,555 194,158 192,445  
Sales 6,212 5,865 12,163 11,826  
Other 365 1,687 1,061 1,915  
Total revenues 104,792 103,107 207,382 206,186  
Costs and expenses:          
Rental, selling and general expenses 69,799 64,935 135,380 128,174  
Cost of sales 3,700 3,361 7,187 7,271  
Restructuring expenses 538 1,324 1,437 3,572  
Depreciation and amortization 13,930 14,369 27,438 27,746  
Total costs and expenses 87,967 83,989 171,442 166,763  
Income from operations 16,825 19,118 35,940 39,423  
Other income (expense):          
Interest income 2,664 2,653 5,314 5,307  
Interest expense (11,328) (10,519) (22,254) (21,388)  
Debt extinguishment expense   (9,192)   (9,192)  
Deferred financing costs write-off   (2,271)   (2,271)  
Income before income tax provision 8,161 (211) 19,000 11,879  
Income tax provision 3,655 924 8,248 6,569  
Net income 4,506 (1,135) 10,752 5,310  
Non-Guarantors          
Revenues:          
Rental 19,636 21,218 38,435 41,684  
Sales 2,189 477 4,216 1,407  
Other 73 47 184 105  
Total revenues 21,898 21,742 42,835 43,196  
Costs and expenses:          
Rental, selling and general expenses 13,051 13,102 25,829 26,165  
Cost of sales 1,708 317 3,333 1,018  
Depreciation and amortization 1,812 1,900 3,568 3,700  
Total costs and expenses 16,571 15,319 32,730 30,883  
Income from operations 5,327 6,423 10,105 12,313  
Other income (expense):          
Interest income 2   2    
Interest expense (129) (136) (255) (405)  
Foreign currency exchange (18) (4) (27) (4)  
Income before income tax provision 5,182 6,283 9,825 11,904  
Income tax provision 911 1,076 1,648 2,144  
Net income $ 4,271 $ 5,207 $ 8,177 $ 9,760