Consolidated and Combined Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Statement [Abstract]
Revenues	$ 1,757,295	$ 1,486,029	$ 1,767,651
Costs and expenses
Cost of operations	1,449,138	1,266,996	1,331,170
Research and development costs	16,543	18,483	21,043
Losses on asset disposals and impairments	14,597	1,752	1,181
Selling, general and administrative expenses	239,968	225,271	204,070
Restructuring activities and spin-off transaction costs	14,946	20,183	18,343
Total costs and expenses	1,735,192	1,532,685	1,575,807
Equity in income (loss) of investees	(242)	8,681	18,387
Operating income (loss)	21,861	(37,975)	210,231
Other income (expense)
Interest income	618	1,060	1,276
Interest expense	(1,059)	(492)	(462)
Other, net	(1,215)	789	1,444
Total other income (expense)	(1,656)	1,357	2,258
Income (loss) before income tax expense (benefit)	20,205	(36,618)	212,489
Income tax expense (benefit)	3,671	(24,728)	72,011
Income (loss) from continuing operations	16,534	(11,890)	140,478
Income (loss) from discontinued operations, net of tax	2,803	(14,272)	34,338
Net income (loss)	19,337	(26,162)	174,816
Net income attributable to noncontrolling interest	(196)	(366)	(289)
Net income (loss) attributable to shareholders	19,141	(26,528)	174,527
Income (loss) from continuing operations	16,338	(12,256)	140,189
Income (loss) from discontinued operations, net of tax	$ 2,803	$ (14,272)	$ 34,338
Basic earnings (loss) per common share
Basic EPS continued operations (usd per share)	$ 0.31	$ (0.23)	$ 2.51
Basic EPS discontinued operations (usd per share)	0.05	(0.26)	0.61
Basic EPS (usd per share)	0.36	(0.49)	3.12
Diluted earnings (loss) per common share
Diluted EPS continued operations (usd per share)	0.30	(0.23)	2.49
Diluted EPS discontinued operations (usd per share)	0.06	(0.26)	0.61
Diluted EPS (usd per share)	$ 0.36	$ (0.49)	$ 3.10
Shares used in the computation of earnings per share
Basic (shares)	53,487,071	54,238,631	55,950,875
Diluted (shares)	53,708,983	54,238,631	56,342,709