Consolidated Statements Of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Revenue	$ 515,036	$ 625,539	$ 961,212	$ 1,233,883
Cost of services and products	461,465	530,306	862,786	1,041,170
Gross Margin	53,571	95,233	98,426	192,713
Selling, general and administrative expense	44,181	56,853	89,186	106,234
Income from Operations	9,390	38,380	9,240	86,479
Interest income	2,045	1,442	3,382	1,737
Interest expense	(7,599)	(6,207)	(13,867)	(12,599)
Equity earnings (losses) of unconsolidated affiliates	(394)	263	(1,374)	789
Other income (expense), net	(58)	(1,405)	(2,614)	(7,393)
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest	3,384	32,473	(5,233)	69,013
Provision for income taxes	1,252	10,164	169	21,601
Net Income	$ 2,132	$ 22,309	$ (5,402)	$ 47,412
Cash Dividends declared per Share	$ 0.15	$ 0.27	$ 0.30	$ 0.54
Basic Earnings per Share	$ 0.02	$ 0.23	$ (0.06)	$ 0.48
Weighted Average Number of Shares Outstanding, Basic	98,263	98,060	98,201	98,006
Diluted Earnings per Share	$ 0.02	$ 0.23	$ (0.06)	$ 0.48
Weighted Average Number of Shares Outstanding, Diluted	98,751	98,424	98,201	98,355