Income taxes

3 Months Ended

Mar. 31, 2020

Income Tax Disclosure [Abstract]

Income taxes

Income taxes

Our estimated annual effective tax rate is about 14%, which does not include discrete tax items. This differs from the 21% statutory corporate tax rate due to the effect of U.S. tax benefits.

Provision for income taxes is based on the following:

	For Three Months Ended
	March 31,
	2020			2019
Taxes calculated using the estimated annual effective tax rate	$	166		$	220
Discrete tax items	(116)			(60)
Provision for income taxes	$	50		$	160
Actual effective tax rate	4		%	12		%