Stockholder's Equity - Changes in the Number of Shares Outstanding and Treasury Shares Held by the Company (Details) - shares	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Shares Outstanding [Abstract]
Beginning balance	239,016,924	237,809,823
Common stock issued	3,234,994	1,564,317
Purchase of common stock	(912,344)	(410,019)
Ending balance	241,339,574	238,964,121
Shares Held as Treasury Shares [Abstract]
Beginning balance	7,824,204	7,400,027
Purchase of common stock	912,344	410,019
Retirement of common stock	(447,173)
Ending balance	8,289,375	7,810,046
Ordinary shares issued at the end of the period	249,628,949	246,774,167	246,841,128