UNAUDITED CONSOLIDATED STATEMENT OF CHANGES IN STOCKHOLDERS' EQUITY - 3 months ended Mar. 31, 2018 - USD ($) $ in Thousands	Total		Common Stock	Treasury Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income
Balance at Dec. 31, 2017	$ 11,260,598		$ 487	$ (8,698,829)	$ 5,783,089	$ 13,938,869	$ 236,982
Balance (in shares) at Dec. 31, 2017			62,689,000	(14,217,000)
Increase (Decrease) in Stockholders' Equity
Net income	607,210
Foreign currency translation adjustments, net of tax benefit of $16,023	60,876	[1]					60,876
Net unrealized losses on marketable securities, net of tax benefit of $1,428	(364)	[2]					(364)
Reclassification adjustment for convertible debt in mezzanine	(48,435)				(48,435)
Exercise of stock options and vesting of restricted stock units and/or performance share units	1,161		$ 1		1,160
Exercise of stock options and vesting of restricted stock units and/or performance share units (in shares)			149,000
Repurchase of common stock	$ (731,592)			$ (731,592)
Repurchase of common stock (in shares)	(373,119)			(373,000)
Stock-based compensation and other stock-based payments	$ 71,500				71,500
Conversion of debt	(773,150)				(773,150)
Balance (in shares) at Mar. 31, 2018			62,838,000	(14,590,000)
Balance at Mar. 31, 2018	10,636,343		$ 488	$ (9,430,421)	$ 5,034,164	14,975,706	56,406
Increase (Decrease) in Stockholders' Equity
Cumulative effect of adoption of accounting standard updates	$ 188,539					$ 429,627	$ (241,088)

[1] (1) Foreign currency translation adjustments result from currency fluctuations on the translation of the Company's international non-U.S. Dollar denominated net assets. Foreign currency translation adjustments were favorable for the three months ended March 31, 2018 compared to the three months ended March 31, 2017 because the U.S. Dollar weakened against certain currencies in which the Company's net assets are denominated. During the three months ended March 31, 2018, the Company recorded deferred tax charges of $10.5 million to foreign currency translation adjustments related to its one-time deemed repatriation tax liability recorded at December 31, 2017 and current year foreign earnings subject to U.S. federal and state income tax, resulting from the introduction of the U.S. Tax Cuts and Jobs Act ("the Tax Act"). Prior to January 1, 2018, foreign currency translation adjustments excluded U.S. federal and state income taxes as a result of the Company's intention to indefinitely reinvest the earnings of its international subsidiaries outside of the United States. Foreign currency translation adjustments also include a tax benefit of $26.5 million and $19.7 million for the three months ended March 31, 2018 and 2017, respectively, associated with the Company's Euro-denominated debt, which is designated as a net investment hedge against the impact of currency fluctuations of the Company's Euro-denominated net assets (see Note 8).

[2] (3) Net unrealized (losses) gains on marketable securities for the three months ended March 31, 2018 and 2017 includes net unrealized losses of $1.8 million and net unrealized gains of $353.8 million before tax on marketable securities, respectively, of which net unrealized gains of $32.4 million and $323.7 million, respectively, were exempt from tax in the Netherlands. Net unrealized losses of $34.2 million and net unrealized gains of $30.1 million for the three months ended March 31, 2018 and 2017 were taxable at a 25% tax rate in the Netherlands, resulting in tax benefits of $8.5 million and tax charges of $7.9 million, respectively. The Company also recorded U.S. tax charges of $7.1 million for the three months ended March 31, 2018 related to these investments.