Cash flow information (Details) - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Interest, net*	$ 63,086	$ 64,596
Income taxes paid, net**	43,448	1,816
AFUDC borrowed	2,000	2,000
Right-of-use assets obtained in exchange for new operating lease liabilities	41,315	46,770	$ 54,880
Property, plant and equipment additions in accounts payable	33,240	34,368	46,119
Accrual for holdback payment related to a business combination	5,000	0	0
Debt assumed in connection with a business combination	0	1,163	$ 1,163
Continuing and discontinued operations
Income taxes paid, net**	$ 43,500	$ 2,000