CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) $ in Thousands	Common Shares	Capital in Excess of Par Value	Accumulated Other Comprehensive Income	Retained Earnings	Treasury Shares	Non-controlling Interest	Total
Balance at the beginning of the period at Dec. 31, 2014	$ 328	$ 2,452,261	$ 77,522	$ 3,573,172	$ (1,194,664)	$ 10,170	$ 4,918,789
Balance (in shares) at Dec. 31, 2014	328,196
Increase (Decrease) in Equity
Net income (loss)				(209,021)		(453)	(209,474)
Dividends to shareholders ($0.06 per share)				(52,489)			(52,489)
Repurchase of treasury shares					(78,399)		(78,399)
Other comprehensive income (loss), net of tax			(99,085)			(1,194)	(100,279)
Issuance of common shares for stock options exercised, net of surrender of unexercised stock options		1,198					1,198
Issuance of common shares for stock options exercised (in shares)	130
Share-based compensation		39,024					39,024
Other	$ 3	(7,537)				563	(6,971)
Other (in shares)	2,269
Balance at the end of the period at Sep. 30, 2015	$ 331	2,484,946	(21,563)	3,311,662	(1,273,063)	9,086	4,511,399
Balance (in shares) at Sep. 30, 2015	330,595
Balance at the beginning of the period at Dec. 31, 2015	$ 331	2,493,100	(47,593)	3,131,134	(1,294,262)	11,158	4,293,868
Balance (in shares) at Dec. 31, 2015	330,526
Increase (Decrease) in Equity
Net income (loss)				(694,155)		(990)	(695,145)
Dividends to shareholders ($0.06 per share)				(50,926)			(50,926)
Repurchase of treasury shares					(1,687)		(1,687)
Other comprehensive income (loss), net of tax			35,668			371	36,039
Issuance of common shares for stock options exercised, net of surrender of unexercised stock options		562					562
Issuance of common shares for stock options exercised (in shares)	57
Share-based compensation		24,070					24,070
Other	$ 2	(4,315)				(3,774)	(8,087)
Other (in shares)	2,424
Balance at the end of the period at Sep. 30, 2016	$ 333	$ 2,513,417	$ (11,925)	$ 2,386,053	$ (1,295,949)	$ 6,765	$ 3,598,694
Balance (in shares) at Sep. 30, 2016	333,007