Equity - Non-controlling Interest in Subsidiaries and Stock Warrants (Details) - $ / shares		12 Months Ended
	Nov. 14, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Joint Ventures
Ownership interest in joint venture percentage by parent		55.00%
Ownership interest in joint venture percentage by noncontrolling owners		45.00%
Warrants
Number of warrants exercised		3,194,787	0	0
Warrants exercise price (in dollars per share)		$ 16.93
Number of warrants expired	5,201
Common shares issued for the exercise of warrants		1,088,918