SCHEDULE II. VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Allowance for Doubtful Accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period		$ 15,119	$ 6,638	$ 17,253
Charged to Cost and Expenses		13,047	9,892	10,175
Due to Currency Translation Adjustments		(1,585)	(969)	(191)
Other	[1]	(932)	(442)	(20,599)
Balance at End of Period		25,649	15,119	6,638
Deferred Tax Assets - Valuation Allowance
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period		131,422	127,164	126,078
Charged to Cost and Expenses		13,175	24,332	4,618	[2]
Due to Currency Translation Adjustments		(11,519)	(9,254)	(5,769)
Other		(22,398)	(10,820)	(2,237)	[3]
Balance at End of Period		110,680	131,422	$ 127,164
Infrastructure Transaction
Valuation and Qualifying Accounts Disclosure [Line Items]
Non-cash tax expense		0	$ 8,000
UK tax rate changes [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Non-cash tax expense		$ 0

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