Income taxes - Schedule of Reconciliation of Effective Tax Rate (Details)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
U.S. statutory tax rate	21.00%	21.00%	21.00%
Increase (decrease) in taxes resulting from:
State taxes (net of federal income tax benefit)	2.70%	2.60%	3.30%
Uncertain tax positions, settlements and lapse of statutes of limitations	0.00%	0.30%	(0.10%)
Valuation allowance on equity method investment	0.60%	0.00%	0.40%
Other valuation allowances, tax rate changes, & deferred adjustments	(0.60%)	(1.70%)	(0.10%)
Non-deductible transaction costs	0.50%	0.10%	0.00%
Net excess benefits or expense on share-based payments	(0.30%)	(0.20%)	(0.10%)
Other, net	0.40%	0.00%	(0.20%)
Effective tax rate	24.30%	22.10%	24.20%