Quarterly financial information (unaudited) (Tables)

12 Months Ended

Dec. 31, 2017

Quarterly Financial Information Disclosure [Abstract]

Schedule of Historical Unaudited Quarterly Financial Data

The following tables set forth the historical unaudited quarterly financial data for the periods indicated ($ in thousands):

	For the three months ended
	December 31, 2017			September 30, 2017			June 30, 2017			March 31, 2017
Total revenues	$	126,538		$	118,342		$	140,598		$	174,067
Operating income	4,035			5,719			22,599			56,316
Net (loss) income	(11,683		)	(5,667		)	(10,530		)	27,639
Net (loss) income available to ordinary shareholders	$	(11,683	)	$	(5,667	)	$	(11,409	)	$	19,717
(Losses) earnings per share - basic	$	(0.11	)	$	(0.05	)	$	(0.11	)	$	0.21
(Losses) earnings per share - diluted	$	(0.11	)	$	(0.05	)	$	(0.11	)	$	0.21

	For the three months ended
	December 31, 2016			September 30, 2016			June 30, 2016			March 31, 2016
Total revenues	$	120,121		$	114,114		$	127,300		$	159,956
Operating income	2,304			11,203			18,655			52,469
Net (loss) income	(24,615		)	(1,560		)	9,854			36,537
Net (loss) income available to ordinary shareholders	$	(35,127	)	$	(13,029	)	$	(1,157	)	$	25,853
(Losses) earnings per share - basic	$	(0.70	)	$	(0.26	)	$	(0.02	)	$	0.28
(Losses) earnings per share - diluted	$	(0.70	)	$	(0.26	)	$	(0.02	)	$	0.28