UNAUDITED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Tax (benefit) associated with gain (loss) on components of foreign currency translation	$ 36,381	$ (100,608)	$ 20,358	$ (120,341)
Reclassification of net unrealized gains on marketable equity securities to retained earnings, tax/(benefit)	0	0	57,597	0
Tax (benefit) associated with gain (loss) on marketable securities	430	8,076	(998)	15,931
Net unrealized (losses) gains on marketable securities, before tax	(4,300)	195,000	(6,100)	548,800
Tax exempt net unrealized (losses) gains on marketable securities, before tax, in the Netherlands	(15,600)	161,400	16,800	485,100
Taxable net unrealized (losses) gains on marketable securities, before tax	11,300	33,600	(22,900)	63,700
Tax and Customs Administration, Netherlands
Tax (benefit) associated with gain (loss) on marketable securities	2,800	8,000	(5,700)	15,900
Domestic Tax Authority [Member]
Tax (benefit) associated with gain (loss) on marketable securities	(2,400)		4,700	0
Currency translation adjustment on deemed repatriation tax liability [Member]
Tax (benefit) associated with gain (loss) on components of foreign currency translation	(21,000)		(10,500)	0
Net Investment Hedging
Tax (benefit) associated with gain (loss) on components of foreign currency translation	$ 57,300	$ (100,600)	$ 30,800	$ (120,300)