CONSOLIDATED STATEMENT OF SHAREHOLDERS' EQUITY (Parenthetical) - shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Common stock shares issued to acquire VLCC vessels (in shares)		31,465,989
Issuance of shares pursuant to purchase commitment (in shares)		483,970
Issuance of common stock (in shares)		15,000,000
Issuance of common stock for vested 2015 and 2016 restricted stock units (in shares)	278,483	574,546
Issuance of common stock for exercise of over-allotment option (in shares)		1,882,223
Class B common stock
Issuance of common stock (in shares)			10,688,828