Quarterly Financial Data (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2018

Quarterly Financial Information Disclosure [Abstract]

Summary of Unaudited Quarterly Results of Operations

The following is a summary of the unaudited quarterly results of operations for the years ended December 31, 2018 and 2017 (in thousands, except per share amounts).

	2018
	March 31,			June 30,			September 30,			December 31,
Revenue	$	266,090		$	232,641		$	224,249		$	199,023
Operating expenses		204,750			205,102			198,607			181,824
Gross margin		61,340			27,539			25,642			17,199
Corporate general and administrative expenses		10,028			9,993			10,279			8,873
Operating income		51,312			17,546			15,363			8,326
Other (expense) income:
Interest expense		(1,780	)		(1,817	)		(1,614	)		(1,434	)
Gain on sale of operations, net		663			—			—			362
Other (expense) income, net		(1,229	)		630			3,143			(9,631	)
Total other (expense) income, net		(2,346	)		(1,187	)		1,529			(10,703	)
Income (loss) from continuing operations before    income tax expense		48,966			16,359			16,892			(2,377	)
Income tax expense (benefit)		13,156			3,238			3,297			(1,424	)
Income (loss) from continuing operations		35,810			13,121			13,595			(953	)
Gain (loss) from operations of discontinued operations,    net of tax		41			(15	)		(9	)		(20	)
Net income (loss)	$	35,851		$	13,106		$	13,586		$	(973	)
Earnings (loss) per share:
Basic:
Continuing operations	$	0.66		$	0.24		$	0.25		$	(0.02	)
Discontinued operations		—			—			—			—
Net income (loss)	$	0.66		$	0.24		$	0.25		$	(0.02	)
Diluted:
Continuing operations	$	0.64		$	0.23		$	0.24		$	(0.02	)
Discontinued operations		—			—			—			—
Net income (loss)	$	0.64		$	0.23		$	0.24		$	(0.02	)
Basic weighted average common shares		54,071			54,594			54,794			54,775
Diluted weighted average common shares		55,924			56,437			56,740			56,580

	2017
	March 31,			June 30,			September 30,			December 31,
Revenue	$	241,459		$	211,016		$	207,723		$	195,142
Operating expenses		192,766			188,120			184,723			189,975
Gross margin		48,693			22,896			23,000			5,167
Corporate general and administrative expenses		8,768			9,232			7,979			7,316
Operating income (loss)		39,925			13,664			15,021			(2,149	)
Other income:
Interest expense		(1,517	)		(1,692	)		(1,777	)		(1,689	)
Gain on sale of operations, net		22			23			—			—
Other income, net		2,737			3,764			2,792			5,196
Total other income, net		1,242			2,095			1,015			3,507
Income from continuing operations before income    tax expense		41,167			15,759			16,036			1,358
Income tax expense (benefit)		16,141			4,343			6,172			(3,368	)
Income from continuing operations		25,026			11,416			9,864			4,726
(Loss) gain from operations of discontinued    operations, net of tax		(152	)		(418	)		(206	)		121
Net income	$	24,874		$	10,998		$	9,658		$	4,847
Earnings (loss) per share:
Basic:
Continuing operations	$	0.47		$	0.21		$	0.18		$	0.09
Discontinued operations		—			(0.01	)		—			—
Net income	$	0.47		$	0.20		$	0.18		$	0.09
Diluted:
Continuing operations	$	0.45		$	0.20		$	0.18		$	0.08
Discontinued operations		—			(0.01	)		—			—
Net income	$	0.45		$	0.19		$	0.18		$	0.08
Basic weighted average common shares		53,293			53,968			54,142			54,034
Diluted weighted average common shares		55,214			55,831			55,827			55,822