Income taxes (Tables)

9 Months Ended

Sep. 30, 2020

Income Tax Disclosure [Abstract]

Provision for income taxes

Provision for income taxes is based on the following:

	For Three Months Ended						For Nine Months Ended
	September 30,						September 30,
	2020			2019			2020			2019
Taxes calculated using the estimated annual effective tax rate	$	231		$	257		$	561		$	715
Discrete tax items	3			(102)			(378)			(191)
Provision for income taxes	$	234		$	155		$	183		$	524
Actual effective tax rate	15		%	10		%	4		%	12		%