Stockholder's Equity - Changes in the Number of Shares Outstanding and Treasury Shares Held by the Company (Details) - shares	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Jun. 30, 2017	Apr. 30, 2017	Dec. 31, 2016
Shares Outstanding [Abstract]
Beginning balance	241,388,277	239,016,924
Common stock issued	43,634,232	3,234,994
Purchase of common stock	(1,013,749)	(912,344)
Ending balance	284,008,760	241,339,574
Shares Held as Treasury Shares [Abstract]
Beginning balance	8,302,004	7,824,204
Purchase of common stock	1,013,749	912,344
Retirement of common stock	(821,586)	(447,173)
Ending balance	8,494,167	8,289,375
Common stock, shares issued	292,502,927	249,628,949	40,800,000	40,800,000	249,690,281