Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Tax carryforwards
Period of time subject to a separate corporate income tax		5 years
(Benefit) Provision for Income Taxes		$ 37,713	$ (97,275)	$ 62,127
Net operating loss carryforwards, tax effected		69,290	64,718
Tax benefit (deficiency) on issuance of shares under employee stock purchase plan and option plans and stock-based compensation		$ 327	$ (60)	$ 2,389
Federal tax rate		35.00%	35.00%
Tax rate		23.30%	(43.50%)	38.90%
Foreign earnings repatriated to utilize both current and carryforward foreign tax credits				$ 252,700
Foreign earnings repatriated to utilize both current and carryforward foreign tax credits which were previously subject to U.S. taxes				65,200
Increase in tax provision from continuing operations resulting from foreign tax credit carryforwards				63,504
Decrease in tax provision from current year foreign tax credits		$ (33,509)		(18,753)
Reversal of valuation allowances related to foreign tax credit carryforwards				23,301
Net increase in tax provision from continuing operations				21,450
Net tax (expenses) benefit for the revaluation of certain current and deferred tax assets and liabilities associated REIT conversion			$ 212,151
Increase in tax provision due to certain amended tax returns to reflect tax accounting method changes consistent with REIT conversion	$ 9,067		29,298
Increase in Tax Provision from Continuing Operations Due to Conversion to REIT			46,356
Tax adjustment relating to REIT		(51,625)	(63,333)	0
Increase (decrease) in gross interest and penalties recorded		2,173	1,462	1,459
Accrued interest and penalties recorded		$ 7,120	5,884
Normal statute of limitation Period, federal tax purpose		3 years
Unrecognized tax benefits		$ 47,685	55,951	$ 51,146	$ 37,563
Unrecognized tax benefits included in other long-term liabilities		45,256	53,078
Deferred income taxes including unrecognized tax benefits		2,429	$ 2,873
Unrecognized tax benefits net of federal benefits		36,062
Unrecognized tax benefits that would impact tax rate		2,730
Foreign
Tax carryforwards
Net operating loss carryforwards, tax effected		$ 66,155
Net operating loss carryforwards subject to valuation allowance (as a percent)		91.00%
Federal
Tax carryforwards
Net operating loss carryforwards, before tax effect		$ 70,820
(Benefit) Provision for Income Taxes		$ 3,022
Minimum
Tax carryforwards
Statute of limitations for state tax		3 years
Maximum
Tax carryforwards
Statute of limitations for state tax		5 years