v3.7.0.1
Condensed Consolidating Financial Information - Guarantor Subsidiaries - Condensed Consolidating Statements of Operations (Detail) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2017
Jun. 30, 2016
Condensed Income Statements, Captions [Line Items]        
Operating revenues, net $ 146,424 $ 167,136 $ 281,042 $ 331,152
Expenses:        
Direct expenses 126,951 152,417 263,464 304,971
Selling, general and administrative expenses 14,247 11,778 27,290 23,451
Total operating expenses 141,198 164,195 290,754 328,422
Loss (gain) on disposal of assets 7 (4,298) 7 (3,939)
Equity in loss of unconsolidated affiliate, net 991 76 1,994 76
Operating (loss) income 4,228 7,163 (11,713) 6,593
Equity in net income of consolidated subsidiaries       0
Interest expense 8,083 7,540 16,278 15,073
Other income, net (705) (494) (1,768) (1,109)
Total expenses 7,378 7,046 14,510 13,964
(Loss) earnings before income taxes (3,150) 117 (26,223) (7,371)
Income tax expense (benefit) 123 (4,160) (7,702) (2,716)
Net (loss) earnings (3,273) 4,277 (18,521) (4,655)
Eliminations [Member]        
Condensed Income Statements, Captions [Line Items]        
Operating revenues, net (2,819)   (2,819)  
Expenses:        
Direct expenses (2,819)   (2,819)  
Selling, general and administrative expenses (4) (325) (9) (498)
Total operating expenses (2,823) (325) (2,828) (498)
Equity in loss of unconsolidated affiliate, net   0   0
Operating (loss) income 4 325 9 498
Equity in net income of consolidated subsidiaries 14,613 7,035 17,243 12,090
Interest expense       0
Other income, net 4 325 9 498
Total expenses 14,617 7,360 17,252 12,588
(Loss) earnings before income taxes (14,613) (7,035) (17,243) (12,090)
Income tax expense (benefit)       0
Net (loss) earnings (14,613) (7,035) (17,243) (12,090)
Parent Company Only (issuer) [Member]        
Condensed Income Statements, Captions [Line Items]        
Operating revenues, net 75,045 89,365 149,329 181,234
Expenses:        
Direct expenses 72,598 89,535 154,942 181,572
Selling, general and administrative expenses 10,916 9,232 21,024 18,275
Total operating expenses 83,514 98,767 175,966 199,847
Loss (gain) on disposal of assets 8 (4,298) 8 (3,939)
Equity in loss of unconsolidated affiliate, net (75) 76 928 76
Operating (loss) income (8,402) (5,180) (27,573) (14,750)
Equity in net income of consolidated subsidiaries (14,613) (7,035) (17,243) (12,090)
Interest expense 8,082 7,534 16,256 15,047
Other income, net (708) (819) (1,776) (1,603)
Total expenses (7,239) (320) (2,763) 1,354
(Loss) earnings before income taxes (1,163) (4,860) (24,810) (16,104)
Income tax expense (benefit) 2,110 (9,137) (6,289) (11,449)
Net (loss) earnings (3,273) 4,277 (18,521) (4,655)
Guarantor Subsidiaries [Member]        
Condensed Income Statements, Captions [Line Items]        
Operating revenues, net 68,857 77,771 126,330 149,918
Expenses:        
Direct expenses 51,806 62,882 104,187 123,399
Selling, general and administrative expenses 3,269 2,871 6,155 5,674
Total operating expenses 55,075 65,753 110,342 129,073
Loss (gain) on disposal of assets (1)   (1)  
Equity in loss of unconsolidated affiliate, net   0   0
Operating (loss) income 13,783 12,018 15,989 20,845
Interest expense 1 6 22 26
Other income, net (1) 0 (1) (4)
Total expenses 0 6 21 22
(Loss) earnings before income taxes 13,783 12,012 15,968 20,823
Income tax expense (benefit) (1,987) 4,977 (1,413) 8,733
Net (loss) earnings 15,770 $ 7,035 17,381 $ 12,090
Non-Guarantor Subsidiaries [Member]        
Condensed Income Statements, Captions [Line Items]        
Operating revenues, net 5,341   8,202  
Expenses:        
Direct expenses 5,366   7,154  
Selling, general and administrative expenses 66   120  
Total operating expenses 5,432   7,274  
Loss (gain) on disposal of assets 0   0  
Equity in loss of unconsolidated affiliate, net 1,066   1,066  
Operating (loss) income (1,157)   (138)  
Interest expense 0   0  
Other income, net 0   0  
Total expenses 0   0  
(Loss) earnings before income taxes (1,157)   (138)  
Income tax expense (benefit) 0      
Net (loss) earnings $ (1,157)   $ (138)