Earnings per share - Schedule of Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Earnings Per Share [Abstract]
Net Income	$ 19,573	$ 79,955	$ 105,771	$ 153,934
Accretion of redeemable noncontrolling interest (see Note 11)	(280)	0	(373)	0
Earnings available to common shareholders	$ 19,293	$ 79,955	$ 105,398	$ 153,934
Weighted average number of common shares outstanding - basic (in shares)	219,128	217,089	218,703	216,900
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Weighted average number of common shares outstanding - diluted (in shares)	219,426	217,905	219,144	217,555
Net income per share – basic (in dollars per share)	$ 0.09	$ 0.37	$ 0.48	$ 0.71
Net income per share – diluted (in dollars per share)	$ 0.09	$ 0.37	$ 0.48	$ 0.71
Restricted stock units
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Effect of dilutive securities (in shares)	25	476	153	327
Performance shares
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Effect of dilutive securities (in shares)	273	315	286	286
Stock options
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Effect of dilutive securities (in shares)	0	25	2	42