Consolidated Statements of Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Parking services revenue
Lease contracts	$ 545.0	$ 570.9	$ 496.6
Management contracts	346.8	350.3	338.3
Total parking services revenue	891.8	921.2	834.9
Reimbursed management contract revenue	723.7	694.7	679.8
Total parking services revenue	1,615.5	1,615.9	1,514.7
Cost of parking services
Lease contracts	505.6	532.8	455.7
Management contracts	209.8	218.3	207.9
Total cost of parking services, gross	715.4	751.1	663.6
Reimbursed management contract expense	723.7	694.7	679.8
Total cost of parking services	1,439.1	1,445.8	1,343.4
Gross profit
Lease contracts	39.4	38.1	40.9
Management contracts	137.0	132.0	130.4
Total gross profit	176.4	170.1	171.3
General and administrative expenses	90.0	97.3	101.5
Depreciation and amortization	33.7	34.0	30.3
Operating income	52.7	38.8	39.5
Other expense (income)
Interest expense	10.5	12.7	17.8
Interest income	(0.5)	(0.2)	(0.4)
Gain on sale of a business	0.0	(0.5)	0.0
Gain on contribution of a business to an unconsolidated entity	0.0	0.0	(4.1)
Equity in losses from investment in unconsolidated entity	0.9	1.7	0.3
Total other expenses (income)	10.9	13.7	13.6
Earnings before income taxes	41.8	25.1	25.9
Income tax expense (benefit)	15.8	4.8	(0.2)
Net income	26.0	20.3	26.1
Less: Net income attributable to noncontrolling interest	2.9	2.9	3.0
Net income attributable to SP Plus Corporation	$ 23.1	$ 17.4	$ 23.1
Net income per common share
Basic (in dollars per share)	$ 1.04	$ 0.78	$ 1.05
Diluted (in dollars per share)	$ 1.03	$ 0.77	$ 1.03
Weighted average shares outstanding
Basic (in shares)	22,238,021	22,189,140	22,009,800
Diluted (in shares)	22,528,122	22,511,759	22,407,343