Condensed Consolidated Statements of Income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Services revenue	$ 381.0	$ 275.7	$ 730.8	$ 522.4
Cost of services (exclusive of depreciation and amortization)	322.2	229.2	620.6	437.6
General and administrative expenses	26.7	22.0	51.2	43.0
Depreciation and amortization	6.5	6.2	13.3	12.5
Operating income	25.6	18.3	45.7	29.3
Other expense (income)
Interest expense	3.5	5.1	8.3	10.9
Interest income	(0.1)	(0.1)	(0.3)	(0.2)
Total other expenses	3.4	5.0	8.0	10.7
Earnings before income taxes	22.2	13.3	37.7	18.6
Income tax expense	5.9	3.5	10.1	4.9
Net income	16.3	9.8	27.6	13.7
Less: Net income attributable to noncontrolling interest	0.9	0.8	1.5	2.4
Net income attributable to SP Plus Corporation	$ 15.4	$ 9.0	$ 26.1	$ 11.3
Net income per common share
Basic (in dollars per share)	$ 0.73	$ 0.42	$ 1.23	$ 0.53
Diluted (in dollars per share)	$ 0.72	$ 0.42	$ 1.22	$ 0.53
Weighted average shares outstanding
Basic (in shares)	21,195,819	21,177,142	21,211,299	21,145,494
Diluted (in shares)	21,356,464	21,390,609	21,347,442	21,347,514
Lease and Management Type Contracts
Services revenue	$ 196.5	$ 141.2	$ 380.9	$ 269.9
Cost of services (exclusive of depreciation and amortization)	137.7	94.7	270.7	185.1
Lease Type Contracts
Services revenue	70.6	50.9	133.2	93.6
Cost of services (exclusive of depreciation and amortization)	55.9	39.5	107.9	74.8
Management Type Contracts
Services revenue	125.9	90.3	247.7	176.3
Cost of services (exclusive of depreciation and amortization)	81.8	55.2	162.8	110.2
Lease Impairment
Cost of services (exclusive of depreciation and amortization)				0.1
Reimbursed Management Type Contract Revenue
Services revenue	184.5	134.5	349.9	252.5
Cost of services (exclusive of depreciation and amortization)	$ 184.5	$ 134.5	$ 349.9	$ 252.5