Condensed Consolidating Financial Information - Guarantor Subsidiaries - Condensed Consolidating Statements of Operations (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014		Mar. 31, 2013
Condensed Income Statements, Captions [Line Items]
Operating revenues, net	$ 197,071		$ 178,968
Expenses:
Direct expenses	158,653		148,203
Selling, general and administrative expenses	9,328		8,266
Management fees
Total operating expenses	167,981		156,469
Loss on disposal of assets, net	1,073		25
Equity in loss of unconsolidated affiliate	41		487
Operating income	27,976		21,987
Equity in net income of consolidated subsidiaries
Interest expense	7,364		7,409
Loss on debt extinguishment	29,216
Other income, net	(91)		(152)
Total expenses	36,489		7,257
(Loss) earnings before income taxes	(8,513)		14,730
Income tax (benefit) expense	(3,192)		5,892
Net (loss) earnings	(5,321)		8,838
Parent Company Only (issuer) [Member]
Condensed Income Statements, Captions [Line Items]
Operating revenues, net	124,354		112,485
Expenses:
Direct expenses	96,426		90,885
Selling, general and administrative expenses	7,081		6,333
Management fees	(2,909)		(2,659)
Total operating expenses	100,598		94,559
Loss on disposal of assets, net	115		25
Equity in loss of unconsolidated affiliate	41		487
Operating income	23,600		17,414
Equity in net income of consolidated subsidiaries	(2,735)		(2,744)
Interest expense	7,364		7,409
Loss on debt extinguishment	29,216
Other income, net	(91)		(152)
Total expenses	33,754		4,513
(Loss) earnings before income taxes	(10,154)		12,901
Income tax (benefit) expense	(4,833)		4,063
Net (loss) earnings	(5,321)		8,838
Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Operating revenues, net	72,717	[1]	66,483	[1]
Expenses:
Direct expenses	62,227	[1]	57,318	[1]
Selling, general and administrative expenses	2,247	[1]	1,933	[1]
Management fees	2,909	[1]	2,659	[1]
Total operating expenses	67,383	[1]	61,910	[1]
Loss on disposal of assets, net	958	[1]		[1]
Equity in loss of unconsolidated affiliate		[1]		[1]
Operating income	4,376	[1]	4,573	[1]
Equity in net income of consolidated subsidiaries		[1]		[1]
Interest expense		[1]		[1]
Loss on debt extinguishment		[1]
Other income, net		[1]		[1]
Total expenses		[1]		[1]
(Loss) earnings before income taxes	4,376	[1]	4,573	[1]
Income tax (benefit) expense	1,641	[1]	1,829	[1]
Net (loss) earnings	2,735	[1]	2,744	[1]
Eliminations [Member]
Condensed Income Statements, Captions [Line Items]
Operating revenues, net
Expenses:
Direct expenses
Selling, general and administrative expenses
Management fees
Total operating expenses
Loss on disposal of assets, net
Equity in loss of unconsolidated affiliate
Operating income
Equity in net income of consolidated subsidiaries	2,735		2,744
Interest expense
Loss on debt extinguishment
Other income, net
Total expenses	2,735		2,744
(Loss) earnings before income taxes	(2,735)		(2,744)
Income tax (benefit) expense
Net (loss) earnings	$ (2,735)		$ (2,744)

[1] Foreign subsidiaries represent minor subsidiaries and are included in the guarantors' subsidiaries amounts.