Summary Of Major Accounting Policies Summary of Major Accounting Policies - Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Jan. 01, 2018	Dec. 31, 2017
Accounting Policies [Abstract]
Interest Costs, Capitalized During Period	$ 1,896		$ 1,100	$ 5,305	$ 3,331
Accounts receivable, billed	345,803			345,803
Revenues	519,300	$ 478,674	476,120	1,414,387	1,437,332
Revenue, adjusted				1,426,939
effect of change, revenue				12,552
Cost of Goods and Services Sold	471,665		421,235	1,318,196	1,284,021
Cost of services and products, adjusted				1,332,238
Effect of change, cost of services and products				14,042
Income Tax Expense (Benefit)	61,135		3,935	70,317	4,104
Income taxes, adjusted				70,105
Net Income (Loss) Attributable to Parent				(148,188)
Effect of change, income taxes				(212)
Accounts Receivable, Net, Current	579,205			579,205			$ 476,903
Effect of change, total accounts receivable	(11,745)			(11,745)		$ 7,993
Effect of change, accounts receivable	0			0		(163,963)
Total accounts receivable, adjusted	567,460			567,460		484,896
Accounts receivable, adjusted	345,803			345,803		312,940
Inventory, Net	189,119			189,119			215,282
Inventory, adjusted	208,478			208,478		181,095
Accrued liabilities, excluding deferred revenue	338,272			338,272
Unbilled Receivables, Current	0			0		171,956	0
Contract assets, current, adjusted	0			0
Unbilled accounts receivable, current, adjusted	221,657			221,657
Contract assets, current	233,402			233,402
Effect of change, contract assets	(233,402)			(233,402)
Effect of change, unbilled accounts receivable	221,657			221,657
Inventory, Gross							215,282
Accrued Liabilities, Current	364,558			364,558			350,258
Accrued liabilities, (excl deferred revenue) adjusted	337,951			337,951		287,213
Total accrued liabilities, adjusted	372,920			372,920		324,803
Effect of change, accrued liabilities	(321)			(321)		(63,045)
Effect of change, total accrued liabilities	8,362			8,362		(25,455)
Deferred Revenue	26,286			26,286		37,590	0
Effect of change, deferred revenue	8,683			8,683
Deferred revenue without adoption of ASC 606	34,969			34,969
Effect of change, inventory	19,359			19,359		(34,187)
Other Liabilities, Noncurrent	163,722			163,722			131,323
Other long-term liabilities, adjusted	163,712			163,712		131,121
Effect of change, other long -term liabilities	(10)			(10)		(202)
Retained Earnings (Accumulated Deficit)	2,268,687			2,268,687		2,416,875	$ 2,417,412
Effect of change, retained earnings	(741)			(741)		$ (537)
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	(65,979)		$ (1,768)	(148,188)	$ (7,170)
Effect of change, Net Income				(1,278)
Retained earnings, adjusted	$ 2,267,946			2,267,946
Net income, adjusted				$ (149,466)