Central Parking Finance Trust PFD TR CV SECS (CRLKP) 10-Q 1 Nov 18 2018 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2018	Oct. 31, 2018
Document and Entity Information
Entity Registrant Name	SP Plus Corp
Entity Central Index Key	1,059,262
Document Type	10-Q
Document Period End Date	Sep. 30, 2018
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Common Stock, Shares Outstanding (in shares)		22,740,442
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q3

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Assets
Cash and cash equivalents	$ 20.2	$ 22.8
Notes and accounts receivable, net	136.4	122.3
Prepaid expenses and other	13.1	15.5
Total current assets	169.7	160.6
Leasehold improvements, equipment and construction in progress, net	26.3	27.4
Other assets
Advances and deposits	4.2	4.1
Other intangible assets, net	50.1	54.1
Favorable acquired lease contracts, net	18.5	23.3
Equity investments in unconsolidated entities	9.9	18.6
Other assets, net	19.1	18.3
Deferred taxes	15.8	15.9
Cost of contracts, net	8.2	8.9
Goodwill	431.6	431.7
Total other assets	557.4	574.9
Total assets	753.4	762.9
Liabilities and stockholders’ equity
Accounts payable	93.5	102.8
Accrued rent	22.8	23.2
Compensation and payroll withholdings	22.4	22.2
Property, payroll and other taxes	10	6.8
Accrued insurance	18	18.9
Accrued expenses	30.4	25.5
Current portion of obligations under Restated Credit Facility and other long-term borrowings	20.9	20.6
Total current liabilities	218	220
Long-term borrowings, excluding current portion
Obligations under Restated Credit Facility	85.8	132
Other long-term borrowings	1.1	1.2
Long-term borrowings, excluding current portion	86.9	133.2
Unfavorable acquired lease contracts, net	26.3	31.5
Other long-term liabilities	63.5	65.1
Total noncurrent liabilities	176.7	229.8
Stockholders’ equity
Preferred stock, par value $0.01 per share; 5,000,000 shares authorized as of September 30, 2018 and December 31, 2017; no shares issued	0	0
Common stock, par value $0.001 per share; 50,000,000 shares authorized as of September 30, 2018 and December 31, 2017; 22,729,564 and 22,542,672 shares issued and outstanding as of September 30, 2018 and December 31, 2017, respectively	0	0
Treasury stock, at cost; 305,183 shares as of September 30, 2018 and December 31, 2017, respectively	(7.5)	(7.5)
Additional paid-in capital	256.7	254.6
Accumulated other comprehensive loss	(1.6)	(1.2)
Retained earnings	111.1	67
Total SP Plus Corporation stockholders’ equity	358.7	312.9
Noncontrolling interest	0	0.2
Total stockholders’ equity	358.7	313.1
Total liabilities and stockholders’ equity	$ 753.4	$ 762.9

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	50,000,000	50,000,000
Common stock, shares issued (in shares)	22,729,564	22,542,672
Common stock, shares outstanding (in shares)	22,729,564	22,542,672
Treasury Stock, Shares (in shares)	305,183	305,183

Condensed Consolidated Statemen

Condensed Consolidated Statements of Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Parking services revenue	$ 362.1	$ 392.7	$ 1,091.2	$ 1,198.1
Cost of parking services	317.1	346.8	955.6	1,054.2
Gross profit	45	45.9	135.6	143.9
General and administrative expenses	18.7	19.6	63.3	63.3
Depreciation and amortization	4.2	4.9	12.7	16.3
Operating income	22.1	21.4	59.6	64.3
Other expenses (income)
Interest expense	2.1	2.2	6.5	7.1
Interest income	(0.1)	(0.2)	(0.3)	(0.5)
Gain on sale of a business	0	0	0	(0.1)
Equity in losses (earnings) from investment in unconsolidated entity	0	0.1	(10.1)	0.5
Total other expenses (income)	2	2.1	(3.9)	7
Earnings before income taxes	20.1	19.3	63.5	57.3
Income tax expense	5.6	7.3	16.9	21.3
Net income	14.5	12	46.6	36
Less: Net income attributable to noncontrolling interest	1	0.8	2.5	2.6
Net income attributable to SP Plus Corporation	$ 13.5	$ 11.2	$ 44.1	$ 33.4
Net income per common share
Basic (in dollars per share)	$ 0.60	$ 0.51	$ 1.97	$ 1.51
Diluted (in dollars per share)	$ 0.60	$ 0.50	$ 1.95	$ 1.48
Weighted average shares outstanding
Basic (in shares)	22,439,884	22,203,023	22,370,789	22,186,556
Diluted (in shares)	22,626,746	22,523,036	22,607,274	22,501,378
Lease type contracts
Parking services revenue	$ 104.7	$ 140.9	$ 311.6	$ 422.6
Cost of parking services	94.2	131	283.2	387
Gross profit	10.5	9.9	28.4	35.6
Management type contracts
Parking services revenue	82.6	86.7	264.8	262.8
Cost of parking services	48.1	50.7	157.6	154.5
Gross profit	34.5	36	107.2	108.3
Lease and Management type contracts
Parking services revenue	187.3	227.6	576.4	685.4
Cost of parking services	142.3	181.7	440.8	541.5
Reimbursed management type contract
Parking services revenue	174.8	165.1	514.8	512.7
Cost of parking services	$ 174.8	$ 165.1	$ 514.8	$ 512.7

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 14.5	$ 12	$ 46.6	$ 36
Other comprehensive income (expense)	0.1	0.1	(0.4)	0.2
Comprehensive income	14.6	12.1	46.2	36.2
Less: Comprehensive income attributable to noncontrolling interest	1	0.8	2.5	2.6
Comprehensive income attributable to SP Plus Corporation	$ 13.6	$ 11.3	$ 43.7	$ 33.6

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Operating activities
Net income	$ 46.6	$ 36
Adjustments to reconcile net income to net cash provided by operations:
Depreciation and amortization	13.4	16.9
Net accretion of acquired lease contracts	(0.5)	(1.2)
Loss on sale of equipment	0	0.1
Net equity in earnings of unconsolidated entities (net of distributions)	(0.4)	(8.6)
Gain on sale of equity method investment in unconsolidated entity	(10.1)	(0.1)
Amortization of debt issuance costs	0.6	0.6
Amortization of original discount on borrowings	0.4	0.4
Non-cash stock-based compensation	2.1	3.2
Provisions for losses on accounts receivable	0.2	0.2
Deferred income taxes	0.1	(1.5)
Changes in operating assets and liabilities
Notes and accounts receivable	(14.4)	(4.6)
Prepaid assets	2.1	3.5
Other assets	(0.4)	(1.9)
Accounts payable	(9.2)	(14.1)
Accrued liabilities	5.1	(7.5)
Net cash provided by operating activities	35.6	21.4
Investing activities
Purchase of leasehold improvements and equipment	(6.7)	(4.9)
Proceeds from sale of equipment and contract terminations	0.2	0.9
Proceeds from sale of equity method investment in unconsolidated entity	19.3	8.4
Cash received from sale of a business, net	0	0.6
Cost of contracts purchased	(0.8)	(0.6)
Net cash provided by investing activities	12	4.4
Financing activities
Payments on revolver (Restated Credit Facility)	(101.6)	(308.7)
Proceeds from revolver (Restated Credit Facility)	104.8	301.5
Payments on term loan (Restated Credit Facility)	(50)	(15)
Payments on other long-term borrowings	(0.3)	(0.2)
Distribution to noncontrolling interest	(2.6)	(2.4)
Payments of debt issuance costs and original discount on borrowings	(0.1)	(0.1)
Net cash used in financing activities	(49.8)	(24.9)
Effect of exchange rate changes on cash and cash equivalents	(0.4)	0.3
(Decrease) increase in cash and cash equivalents	(2.6)	1.2
Cash and cash equivalents at beginning of year	22.8	22.2
Cash and cash equivalents at end of period	20.2	23.4
Cash paid during the period for
Interest	5.5	6.2
Income taxes, net	11.8	21.4
Non-cash transactions
Capital lease obligations incurred to acquire equipment	$ 0.1	$ 0

Significant Accounting Policies

Significant Accounting Policies and Practices	9 Months Ended
	Sep. 30, 2018
Accounting Policies [Abstract]
Significant Accounting Policies and Practices	Significant Accounting Policies and Practices The Company SP Plus Corporation (the “Company”) provides parking management, ground transportation and other ancillary services to commercial, institutional and municipal clients in urban markets and airports across the United States, Canada and Puerto Rico. These services include a comprehensive set of on-site parking management and ground transportation services, which include facility maintenance, event logistics services, security services, training, scheduling and supervising all service personnel as well as providing customer service, marketing, and accounting and revenue control functions necessary to facilitate the operation of clients’ facilities or events. The Company also provides a range of ancillary services such as airport and municipal shuttle operations, valet services, taxi and livery dispatch services, security services and municipal meter revenue collection and enforcement services. Basis of Presentation The accompanying unaudited Condensed Consolidated Financial Statements of the Company have been prepared in accordance with accounting principles generally accepted in the United States ("U.S. GAAP") for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, certain information and disclosures normally included in the Condensed Consolidated Balance Sheets, Statements of Income, Comprehensive Income and Cash Flows prepared in conformity with U.S. GAAP have been condensed or omitted as permitted by such rules and regulations. In the opinion of management, all adjustments (consisting only of adjustments of a normal and recurring nature) considered necessary for a fair presentation have been included. Operating results for the three and nine-month periods ended September 30, 2018 are not necessarily indicative of the results that might be expected for any other interim period or the fiscal year ending December 31, 2018 . The financial statements presented in this report should be read in conjunction with the Company’s annual Consolidated Financial Statements and notes thereto included in the Annual Report on Form 10-K filed on February 22, 2018. Cash and cash equivalents Cash equivalents represent funds temporarily invested in money market instruments with maturities of three months or less. Cash equivalents are stated at cost, which approximates fair value. Cash and cash equivalents that are restricted as to withdrawal or use under the terms of certain contractual agreements was $0.3 million and $0.3 million as of September 30, 2018 and December 31, 2017 , respectively, and are included within Cash and cash equivalents within the Condensed Consolidated Balance Sheets. Financial Instruments The carrying values of cash, accounts receivable and accounts payable approximate their fair value due to the short-term nature of these financial instruments. Book overdrafts of $26.0 million and $29.0 million are included within Accounts payable within the Condensed Consolidated Balance Sheets as of September 30, 2018 and December 31, 2017 , respectively. Long-term debt has a carrying value that approximates fair value because these instruments bear interest at variable market rates. Equity Investments in Unconsolidated Entities The Company has ownership interests in 29 active partnerships, joint ventures or similar arrangements that operate parking facilities, of which 24 are consolidated under the VIE or voting interest models and 5 are unconsolidated where the Company’s ownership interests range from 30 - 50 percent and for which there are no indicators of control. The Company accounts for such investments under the equity method of accounting, and its underlying share of each investee’s equity is included in Equity investments in unconsolidated entities within the Condensed Consolidated Balance Sheets. As the operations of these entities are consistent with the Company’s underlying core business operations, the equity in earnings of these investments are included in Parking services revenue - lease type contracts within the Condensed Consolidated Statements of Income. Included in equity earnings for the three and nine months ended September 30, 2017 are earnings of $8.5 million from the Company's proportionate share of the net gain of an equity method investees' sale of assets. The equity earnings in these related investments were $0.7 million and $0.6 million for the three months ended September 30, 2018 and 2017 , respectively, and were $1.9 million and $10.6 million for the nine months ended September 30, 2018 and 2017 , respectively. In October 2014, the Company entered into an agreement to establish a joint venture with Parkmobile USA, Inc. and contributed all of the assets and liabilities of its proprietary Click and Park parking prepayment business in exchange for a 30% interest in the newly formed legal entity called Parkmobile, LLC (“Parkmobile”). The Parkmobile joint venture combined two parking transaction engines, with SP Plus contributing the Click and Park® parking prepayment systems, which enables consumers to reserve and pay for parking online in advance and Parkmobile USA contributing its on demand transaction engine that allows consumers to transact real-time payment for parking privileges in both on- and off-street environments. On January 3, 2018, the Company closed a transaction to sell the entire 30% interest in Parkmobile to Parkmobile USA, Inc. for a gross sale price of $19.0 million and in the first quarter of 2018, the Company recognized a pre-tax gain of $10.1 million , net of closing costs, and included in Equity in losses (earnings) from investment in unconsolidated entity within the Condensed Consolidated Statements of Income for the nine months ended September 30, 2018 . The Company historically accounted for its investment in the Parkmobile joint venture using the equity method of accounting, and its underlying share of equity in Parkmobile was included in Equity investments in unconsolidated entities within the Condensed Consolidated Balance Sheets. The equity losses (earnings) in the Parkmobile joint venture were historically included in Equity in losses (earnings) from investment in unconsolidated entity within the Condensed Consolidated Statements of Income. Noncontrolling Interests Noncontrolling interests represent the noncontrolling holders’ percentage share of income or losses from the subsidiaries in which the Company holds a majority, but less than 100 percent, ownership interest and the results of which are consolidated and included within the Condensed Consolidated Financial Statements. Recently Issued Accounting Pronouncements Recently Adopted Accounting Pronouncements In May 2014, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2014-09 "Revenue from Contracts with Customers" (Topic 606) and following its release, the FASB also issued the following additional ASUs updating the topic: • In December 2016, the FASB issued ASU No. 2016-20, Technical Corrections and Improvements to Topic 606, Revenue from Contracts with Customers • In May 2016, the FASB issued ASU No. 2016-12 , Revenue from Contracts with Customers (Topic 606): Narrow-Scope Improvements and Practical Expedients • In April 2016, the FASB issued ASU No. 2016-10, Revenue from Contracts with Customers (Topic 606): Identifying Performance Obligations and Licensing • In March 2016, the FASB issued ASU No. 2016-08, Revenue from Contracts with Customers (Topic 606): Principal versus Agent Considerations (Reporting Revenue Gross versus Net) • In August 2015, the FASB issued ASU No. 2015-14, Revenue from Contracts with Customers (Topic 606): Deferral of the Effective Date Topic 606 supersedes the revenue recognition requirements in ASC 605, Revenue Recognition ( Topic 605 ), and requires entities to recognize revenue when control of the promised goods or services is transferred to customers at an amount that reflects the consideration to which the entity expects to be entitled to in exchange for those goods or services. The Company adopted the provisions of Topic 606 on January 1, 2018 using the modified retrospective transition method and therefore the comparative periods have not been recasted and continue to be reported under the accounting standards in effect for those prior periods presented. The standard has been applied to contracts that have not been completed at the date of initial application. Furthermore and in accordance with Topic 606, the Company has not retrospectively restated the contracts that were modified before the beginning of the earliest reporting period presented. The aggregate effect of all modifications when identifying the satisfied and unsatisfied performance obligations were reflected in determining and allocating the transaction price. The application of these practical expedients did not have a significant impact on the Company’s financial position, results of operations, cash flows and related financial statement disclosures. In May 2017, the FASB issued ASU No. 2017-10, Service Concession Arrangements ( Topic 853 ): Determining the Customer of the Operation Services . Topic 853 further clarifies how operating entities should determine the customer of operation services for transactions within the scope of Topic 853. The Company determined that revenue generated from service concession arrangements, will be accounted for under the guidance of Topic 606 upon adoption of Topic 853. The Company adopted the provisions of Topic 853 on January 1, 2018 and upon the adoption, the Company was required to reclassify certain assets used in service concession arrangements that were previously included in Leasehold improvements, equipment and construction in progress, net, to Other assets, net within the Condensed Consolidated Balance Sheet for September 30, 2018 (as discussed previously, the prior period presented has not been recasted). In addition, the Company has the contractual right to invoice a customer prior to the performance obligation being satisfied in certain contractual arrangements, primarily related to monthly parking arrangements, and therefore effective January 1, 2018; the Company established a contract asset with a corresponding contract liability for the performance obligation expected to be satisfied at a future date. The impact of this change on the Condensed Consolidated Balance Sheet as of September 30, 2018 is as follows: Impact of Changes in Accounting Policies as of September 30, 2018 (millions, unaudited) As Reported Balances without Adoption of Topics 606 and 853 Impact of Adoption Increase/(Decrease) Assets Notes and accounts receivable, net (1) $ 136.4 $ 125.8 $ 10.6 Leasehold improvements, equipment and construction in progress, net (2) 26.3 26.8 (0.5 ) Other assets, net (2) 19.1 18.6 0.5 Liabilities Accrued expenses (1) $ 30.4 $ 19.8 $ 10.6 (1) Approximately $10.6 million and $10.6 million of contract assets and contract liabilities, respectively, were recognized as of September 30, 2018. (2) Leasehold improvements used in service concession arrangements of approximately $0.5 million were reclassified from Leasehold improvements, equipment and construction in progress to Other assets, net, as of September 30, 2018. The adoption of Topics 606 and 853 had no impact to the Company’s Operating income or Net income for the three and nine months ended September 30, 2018. Certain expenses, primarily rental expense for the contractual arrangements that meet the definition of service concession arrangements under Topic 853, have been recorded as a reduction of revenue for the three and nine months ended September 30, 2018 (as discussed above, prior periods have not been recasted). The impact of this change to gross profit and depreciation and amortization for the three and nine months ended September 30, 2018 was as follows: Impact of Changes in Accounting Policies for the Three Months Ended September 30, 2018 Impact of Changes in Accounting Policies for the Nine Months Ended September 30, 2018 (millions, unaudited) As Reported Balances without Adoption of Topics 853 and 606 Impact of Adoption As Reported Balances without Adoption of Topics 853 and 606 Impact of Adoption Increase/(Decrease) Parking services revenue Lease type contracts (1) $ 104.7 $ 138.5 $ (33.8 ) $ 311.6 $ 411.1 $ (99.5 ) Management type contracts 82.6 82.6 — 264.8 264.8 — 187.3 221.1 (33.8 ) 576.4 675.9 (99.5 ) Reimbursed management type contract revenue 174.8 174.8 — 514.8 514.8 — Total parking services revenue 362.1 395.9 (33.8 ) 1,091.2 1,190.7 (99.5 ) Cost of parking services Lease type contracts (1) 94.2 128.0 (33.8 ) 283.2 382.6 (99.4 ) Management type contracts 48.1 48.1 — 157.6 157.6 — 142.3 176.1 (33.8 ) 440.8 540.2 (99.4 ) Reimbursed management type contract expense 174.8 174.8 — 514.8 514.8 — Total cost of parking services 317.1 350.9 (33.8 ) 955.6 1,055.0 (99.4 ) Gross profit Lease type contracts 10.5 10.5 — 28.4 28.5 (0.1 ) Management type contracts 34.5 34.5 — 107.2 107.3 (0.1 ) Total gross profit $ 45.0 $ 45.0 $ — $ 135.6 $ 135.8 $ (0.2 ) Depreciation and amortization $ 4.2 $ 4.3 $ (0.1 ) $ 12.7 $ 13.0 $ (0.3 ) (1) Certain expenses, primarily rental expense for contractual arrangements that meet the definition of a service concession arrangement under Topic 853, of approximately $33.8 million and $99.4 million that would have been previously classified as Cost of parking services - lease type contracts have been classified as a reduction of revenue and included in Parking services revenue - lease type contracts for the three and nine months ended September 30, 2018, respectively. The adoption of Topics 606 and 853 did not result in a cumulative effect on our opening retained earnings and there was no impact to the Company's Condensed Consolidated Statements of Cash Flows. See Note 2. Revenue for further discussion on the impacts of adopting Topics 606 and 853. In May 2017, the FASB issued ASU No. 2017-09, Compensation - Stock Compensation (Topic 718), Scope Modification Accounting . ASU No. 2017-09 clarifies when to account for a change to the terms or conditions of a share-based payment award as a modification. Under the new guidance, modification accounting is required only if the fair value, the vesting conditions, or the classification of the award (as equity or liability) changes as a result of the change in terms or conditions. The guidance is effective prospectively for all companies for annual periods beginning on or after December 15, 2017. Early adoption is permitted. The Company adopted the standard as of January 1, 2018. The standard did not have an impact on the Company’s financial position, results of operations, cash flows and financial statement disclosures. In January 2017, the FASB issued ASU No. 2017-01, Business Combinations - Clarifying the Definition of a Business (Topic 805) . Under ASU No. 2017-01, an entity first determines whether substantially all of the fair value of the gross assets acquired is concentrated in a single identifiable asset or a group of similar identifiable assets. If this threshold is met, the set is not a business. If it’s not met, the entity then evaluates whether the set meets the requirement that a business include, at a minimum, an input and a substantive process that together significantly contribute to the ability to create outputs. Under current guidance, a business consists of (1) inputs, (2) processes applied to those inputs and (3) the ability to create outputs. ASU No. 2017-01 is effective for fiscal years beginning after December 15, 2017, and interim periods within those years. The standard will be applied prospectively to any transactions occurring within the period of adoption. The Company adopted the standard as of January 1, 2018. The standard did not have an impact on the Company’s financial position, results of operations, cash flows and financial statement disclosures. In November 2016, the FASB issued ASU No. 2016-18, Statement of Cash Flows - Restricted Cash (Topic 230) . ASU No. 2016-18 clarifies how entities should present restricted cash and restricted cash equivalents in the statement of cash flows. The guidance requires entities to show the changes in the total of cash, cash equivalents, restricted cash and restricted cash equivalents in the statement of cash flows. As a result, entities will no longer present transfers between cash and cash equivalents and restricted cash and restricted cash equivalents in the statement of cash flows. The guidance, which is based on a consensus of the Emerging Issues Task Force (EITF), is effective for fiscal years beginning after December 15, 2017, and interim periods within those years. The Company adopted this standard as of January 1, 2018. The standard did not have an impact on the Company's financial position, results of operation, cash flows and financial statement disclosures. In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows - Classification of Certain Cash Receipts and Cash Payments (Topic 230) . ASU 2016-15 amends the guidance in ASC 230 related to the classification of certain cash receipts and payments in the statement of cash flows. The primary purpose of the ASU is to reduce the diversity in practice that has resulted from the lack of consistent principles on this topic. The amendment adds or clarifies several statement of cash flow classification issues including: (i) debt prepayment or debt extinguishment costs, (ii) settlement of certain zero-coupon debt instruments, (iii) contingent consideration payments, (iv) proceeds from the settlement of insurance claims, (v) proceeds from the settlement of corporate-owned life insurance policies, (vi) distributions received from equity method investments, (vii) beneficial interest in securitization transactions, and (viii) separately identifiable cash flows and application of the predominance principle. The standard is effective for interim and annual reporting periods beginning after December 15, 2017. The Company adopted this standard as of January 1, 2018. The standard did not have an impact on the Company's financial position, results of operation, cash flows and financial statement disclosures. In January 2016, the FASB issued ASU No. 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities . ASU No. 2016-01 amends various areas of the accounting for financial instruments. Key provisions of the amendment require (i) equity investments to be measured at fair value (except those accounted for under the equity method), (ii) the simplification of equity investment impairment determination, (iii) certain changes to the fair value measurement of financial instruments measured at amortized cost, (iv) the separate presentation, in other comprehensive income, the portion of the total change in the fair value of the liability resulting from a change in the instrument-specific credit risk (given certain conditions), and (v) the evaluation for a valuation allowance on a deferred tax asset related to available-for-sale securities in combination with the Company's other deferred tax assets. ASU No. 2016-01 is effective for interim and annual reporting periods beginning after December 15, 2017. The Company adopted this standard as of January 1, 2018. The standard did not have an impact on the Company's financial position, results of operation, cash flows and financial statement disclosures. Accounting Pronouncements to be Adopted In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842). ASU No. 2016-02 requires lessees to record most leases on the balance sheet and recognize expense, similar to current accounting guidance, on the income statement. Additionally, the classification criteria and the accounting for sales-type and direct financing leases is modified for lessors. Under ASU No. 2016-02, all entities are required to recognize "right-of-use" ("ROU") assets and lease liabilities on the balance sheet for all leases classified as either operating or finance leases. Lease classification will determine recognition of lease-related revenue and expense. Since the release of ASU No. 2016-02, the FASB also issued the following additional ASUs updating the topic: • In January 2018, the FASB issued ASU No. 2018-01, Land Easement Practical Expedient for Transition to Topic 842 • In July 2018, the FASB issued ASU No. 2018-11, Lease (Topic 842): Targeted Improvements • In July 2018, the FASB issued ASU No. 2018-10, Codification Improvements to Topic 842, Leases ASU No. 2016-02 and its related ASUs are effective for interim and annual reporting periods beginning after December 15, 2018. The Company has commenced the process of implementing Topic 842 and has developed a project plan to guide the implementation and assessment of the impact of the standard and other changes to the Company's financial position, results of operations, cash flows and financial statement disclosures. The Company has made progress on this project plan including assessing the Company’s portfolio of leases, understanding key policy elections and considerations under the standard as well as changes to key processes and internal controls. The Company has selected a lease accounting software solution to support the new reporting requirements and has commenced the process of extracting lease data from lease agreements for input into the software solution. The Company will take advantage of the transition package of practical expedients as permitted within ASU No. 2016-02 which among other things allows the Company to carry forward the historical lease classification. The Company will be making an accounting policy election to keep leases with an initial lease term of 12 months or less off of the Consolidated Balance Sheet and therefore there will be no requirement to recognize ROU assets and lease liabilities for these leases. While the Company continues to assess the potential impacts of the new standard, the most significant impact upon adoption will be the recognition of ROU assets and lease liabilities for operating leases. However, the Company does not expect adoption will have a material impact on the Consolidated Statement of Income. The Company expects the accounting for capital leases to remain substantially unchanged. In June 2018, the FASB issued ASU No. 2018-07, Compensation—Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting . Under existing guidance, the accounting for nonemployee share-based payments differs from that applied to employee awards, particularly with regard to the measurement date and the impact of performance conditions. This ASU provides for existing employee guidance will apply to nonemployee share-based transactions (as long as the transaction is not effectively a form of financing), with the exception of specific guidance related to the attribution of compensation cost. The cost of nonemployee awards will continue to be recorded as if the grantor had paid cash for the goods or services. In addition, the contractual term will be able to be used in lieu of an expected term in the option-pricing model for nonemployee awards. ASU No. 2018-07 is effective for all companies for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years. Public business entities may early adopt the guidance for financial statements that have not yet been issued but no earlier than an entity’s adoption date of Topic 606. The Company is currently assessing the impact of adopting the standard on the Company's financial position, results of operations, cash flows and financial statement disclosures. In February 2018, the FASB issued ASU No. 2018-02, Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income . The ASU provides guidance that permits companies to reclassify disproportionate tax effects in accumulated other comprehensive income (AOCI) caused by the Tax Cuts and Jobs Act of 2017 (the "2017 Tax Act") to retained earnings. The FASB refers to these amounts as "stranded tax effects." Companies that elect to reclassify the effects associated with the change in US federal corporate income tax rate must do so for all items within the AOCI. The new guidance also requires all companies to include certain new disclosures in their financial statements, regardless of whether a company opts to make the reclassification. Companies may adopt the new guidance using one of two transition methods: (1) retrospective to each period (or periods) in which the income tax effects of the 2017 Tax Act related to items remaining in AOCI are recognized, or (2) at the beginning of the period of adoption. ASU No. 2018-02 is effective for all companies for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years. Public business entities may early adopt the guidance for financial statements that have not yet been issued. The Company is currently assessing the impact of adopting the standard on the Company's financial position, results of operations, cash flows and financial statement disclosures. In January 2017, the FASB issued ASU No. 2017-04, Intangibles – Goodwill and Other (Topic 350): Simplifying the Accounting for Goodwill Impairment. The new guidance simplifies the accounting for goodwill impairment by removing Step 2 of the goodwill impairment test, which requires a hypothetical purchase price allocation. A goodwill impairment will now be the amount by which a reporting unit’s carrying value exceeds its fair value, not to exceed the carrying amount of goodwill. All other goodwill impairment guidance will remain largely unchanged. Entities will continue to have the option to perform a qualitative assessment to determine if a quantitative impairment test is necessary. The same one-step impairment test will be applied to goodwill at all reporting units, even those with zero or negative carrying amounts. Entities will be required to disclose the amount of goodwill at reporting units with zero or negative carrying amounts. ASU No. 2017-04 is effective for annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2019. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The Company is currently assessing the impact of adopting the standard on the Company's financial position, results of operations, cash flows and financial statement disclosures. In June 2016, the FASB issued ASU No. 2016-13, Credit Losses - Measurement of Credit Losses on Financial Instruments (Topic 326) . The standard significantly changes how entities will measure credit losses for most financial assets and certain other instruments that are not measured at fair value through net income. The standard will replace today’s “incurred loss” approach with an “expected loss” model for instruments measured at amortized cost. For available-for-sale debt securities, entities will be required to record allowances rather than reduce the carrying amount, as they do today under the other-than-temporary impairment model. Entities will apply the standard’s provisions as a cumulative-effect adjustment to retained earnings as of the beginning of the first reporting period in which the guidance is effective. The standard is effective for interim and annual reporting periods beginning after December 15, 2019. The Company is currently assessing the impact of adopting this standard on the Company’s financial position, results of operations, cash flows and financial statement disclosures. In August 2018, the FASB issued ASU No. 2018-15, Intangibles – Goodwill and Other – Internal - Use Software (Subtopic 350-40): Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract. The standard requires a customer in a cloud computing arrangement that is a service contract to follow the internal-use software guidance in Accounting Standards Codification (ASC) 350-40 to determine which implementation costs to capitalize as assets. Capitalized implementation costs related to a hosting arrangement that is a service contract will be amortized over the term of the hosting arrangement, beginning when the module or component of the hosting arrangement is ready for its intended use. The standard is effective for interim and annual reporting periods beginning after December 15, 2019. The Company is currently assessing the impact of adopting this standard on the Company’s financial position, results of operations, cash flows and financial statement disclosures. In August 2018, the FASB issued ASU No. 2018-13, Fair Value Measurement (Topic 820). This standard modifies the disclosures on fair value measurements by removing the requirement to disclose the amount and reasons for transfers between Level 1 and Level 2 of the fair value hierarchy and the policy for timing of such transfers. The ASU expands the disclosure requirements for Level 3 fair value measurements, primarily focused on changes in unrealized gains and losses included in other comprehensive income. The standard is effective for interim and annual reporting periods beginning after December 15, 2019. The Company is currently assessing the impact of adopting this standard on the Company’s financial position, results of operations, cash flows and financial statement disclosures.

Revenue

Revenue	9 Months Ended
	Sep. 30, 2018
Revenue from Contract with Customer [Abstract]
Revenue	Revenue The Company accounts for revenue in accordance with Topics 606 and 853. Topic 606 requires entities to recognize revenue when control of the promised goods or services is transferred to customers at an amount that reflects the consideration to which the entity expects to be entitled to in exchange for those goods or services. See also Note 1. Significant Accounting Policies for further discussion. The Company adopted Topics 606 and 853 on January 1, 2018, using the modified retrospective method of adoption. Contracts with customers and clients The Company accounts for a contract when it has approval and commitment from both parties, the rights of the parties are identified, payment terms are identified, the contract has commercial substance, and collectability of consideration is probable. Once a contract is identified, the Company evaluates whether the combined or single contract should be accounted for as more than one performance obligation. Substantially all of our revenues come from the following two types of arrangements: Lease type and Management type contracts. Parking services revenue - lease type contracts Under lease type arrangements, the Company pays the property owner a fixed base rent or payment, percentage rent or payment that is tied to the facility’s financial performance, or a combination of both. The Company operates the parking facility and is responsible for most operating expenses, but typically is not responsible for major maintenance, capital expenditures or real estate taxes. Performance obligations for parking services revenues related to lease type contracts include parking for transient and monthly parkers. Revenue is recognized over time as the Company provides services. As noted in Note 1. Significant Accounting Policies and in accordance with Topic 853, certain expenses, primarily rental expense for the contractual arrangements that meet the definition of service concession arrangements, are recorded as a reduction of revenue for the three and nine months ended September 30, 2018. Parking services revenue - management type contracts Management type contract revenue consists of management fees, including both fixed and performance-based fees. In exchange for this consideration, the Company has a bundle of performance obligations that include services such as managing the parking facility as well as ancillary services such as accounting, equipment leasing, consulting, insurance and other value-added services. The Company believes that it can generally purchase required insurance for the location at lower rates than clients can obtain on their own because the Company is effectively self-insured for all liability, worker's compensation and health care claims by maintaining a large per-claim deductible. As a result, the Company generates operating income on the insurance provided under our management type contracts by focusing on our risk management efforts and controlling losses. Management type contract revenues do not include gross customer collections at the managed locations as these revenues belong to the property owners rather than to the Company. Management type contracts generally provide the Company with management fees regardless of the operating performance of the underlying facilities. Revenue is recognized over time as the Company provides services. Service concession arrangements Service concession agreements within the scope of Topic 853 include both lease type and management type contracts. Upon the adoption of Topic 853, revenue generated from service concession arrangements, is accounted for under the guidance of Topics 606 and Topic 853. For the three and nine months ended September 30, 2018, certain expenses (primarily rental expense) related to service concession arrangements, previously recorded within Cost of parking services - lease type contracts and Depreciation and amortization, have been recorded as a reduction of Parking service revenue - lease type contracts upon adoption of Topic 853. Contract modifications and taxes Contracts are often modified to account for changes in contract specifications and requirements. The Company considers contract modifications to exist when the modification either changes the consideration due to the Company or creates new performance obligations or changes the existing scope of the contract and related performance obligations. Most of our contract modifications are for services that are not distinct from the existing contract due to the fact that the Company is providing a bundle of performance obligations that are highly inter-related in the context of the contract, and are therefore accounted for as if they were part of that existing contract. Typically, modifications are accounted for prospectively as part of the existing contract. Taxes assessed by a governmental authority that are both imposed on and concurrent with a specific revenue-producing transaction, which are collected by the Company from a customer, are excluded from revenue. Reimbursed management type contract revenue and expense The Company recognizes both revenues and expenses, in equal amounts, that are directly reimbursed from the property owner for operating expenses incurred under a management type contract. The Company has determined it is the principal in these transactions as the nature of our performance obligations is for the Company to provide the services on behalf of the customer. As the principal to these related transactions, the Company has control of the promised services before they are transferred to the customer. Disaggregation of revenue The Company disaggregates its revenue from contracts with customers by type of arrangement for each of our reportable segments. The Company has concluded that such disaggregation of revenue best depicts the overall economic nature, timing and uncertainty of the Company's revenue and cash flows affected by the economic factors of the respective contractual arrangement. See Note 15. Business Unit Segment Information for further information on disaggregation of our revenue by segment. Performance obligations A performance obligation is a promise in a contract to transfer a distinct good or service to the customer or client, and is the unit of account in Topic 606. The contract transaction price is allocated to each distinct performance obligation and recognized as revenue when, or as, the performance obligation is satisfied. The majority of our contracts have a single performance obligation that is not separately identifiable from other promises in the contract and therefore not distinct, comprising the promise to provide a bundle of monthly performance obligations or parking services for transient or monthly parkers. The contract price is generally deemed to be the transaction price. Some management type contracts include performance incentives that are based on variable performance measures. These incentives are constrained at contract inception and recognized once the customer has confirmed that the Company has met the contractually agreed upon performance measures as defined in the contract. Our performance obligations are primarily satisfied over time as the Company provides the related services. Typically, revenue is recognized over time on a straight-line basis as the Company satisfies the related performance obligation. There are certain management type contracts where revenue is recognized based on costs incurred to date plus a reasonable margin. The Company has concluded this is a faithful depiction of how control is transferred to the customer. Performance obligations satisfied at a point in time for the three and nine months ended September 30, 2018 were not significant. The time between completion of the performance obligation and collection of cash is typically not more than 30 - 60 days. In certain contractual arrangements, such monthly parker contracts, cash is collected in advance of the Company commencing its performance obligations under the contractual arrangement. On September 30, 2018, the Company had $106.7 million related to performance obligations that were unsatisfied or partially unsatisfied for which the Company expects to recognize revenue. This amount excludes variable consideration primarily related to contracts where the Company and customer share the gross revenues or operating profit for the location and contracts where transaction prices include performance incentives that are constrained at contract inception. These performance incentives are based on measures that are ascertained exclusively by future performance and therefore cannot be estimated at contract inception by the Company. The Company applies the practical expedient that permits exclusion of information about the remaining performance obligations that have original expected durations of one year or less. The Company expects to recognize our remaining performance obligations as revenue in future periods as follows: (millions, unaudited) Remaining Performance Obligations 2018 $ 13.1 2019 38.3 2020 24.9 2021 12.8 2022 8.0 2023 and thereafter 9.6 Total $ 106.7 Contract balances The timing of revenue recognition, billings and cash collections results in accounts receivable, contract assets and contract liabilities. Accounts receivable represent amounts where the Company has an unconditional right to the consideration and therefore only the passage of time is required for the Company to receive consideration due from the customer. Both lease type and management type contracts have customers and clients where amounts are billed as work progresses or in advance in accordance with agreed-upon contractual terms. Billing may occur subsequent to or prior to revenue recognition, resulting in contract assets and contract liabilities. The Company, on occasion, receives advances or deposits from customers and clients, on both lease and management type contracts, before revenue is recognized, resulting in the recognition of contract liabilities. Contract assets and contract liabilities are reported on a contract-by-contract basis and are included in Notes and accounts receivable, net and Accrued expenses, respectively, on the Condensed Consolidated Balance Sheet as of September 30, 2018. Impairment charges related to accounts receivable for the three and nine months ended September 30, 2018 and 2017, were not significant. There were no impairment charges recorded on contract assets and contract liabilities for the three and nine months ended September 30, 2018. The following table provides information about contract assets and contract liabilities with customers and clients as of September 30, 2018: (millions, unaudited) September 30, 2018 Accounts receivable $ 125.6 Contract asset $ 10.8 Contract liability $ (16.5 ) Changes in contract assets include recognition of additional consideration due from the customer or client once the Company obtains an unconditional right to the consideration offset by reclassifications of contract asset balances to accounts receivable when the Company obtains an unconditional right to consideration, thereby establishing an accounts receivable. The following table provides information about changes to contract asset balances for the nine-month period ended September 30, 2018: (millions, unaudited) Contract Asset Balance as of January 1, 2018 $ 12.2 Additional contract assets 100.0 Reclassification to accounts receivable (101.4 ) Balance as of September 30, 2018 $ 10.8 Changes in contract liability primarily include additional contract liabilities and liquidation of contract liabilities when revenue is recognized. The entire contract liability balance as of January 1, 2018 was recognized as revenue during the nine-month period ended September 30, 2018. The following table provides information about changes to contract liability balances for the nine-month period ended September 30, 2018: (millions, unaudited) Contract Liability Balance as of January 1, 2018 $ (20.5 ) Additional contract liabilities (128.6 ) Recognition of revenue from contract liabilities 132.6 Balance as of September 30, 2018 $ (16.5 ) Cost of contracts, net Cost of contracts, net represents the cost of obtaining contractual rights associated with providing parking services for a lease or management type contracts. The adoption of Topic 606 did not have a significant impact on how the Company previously reported contract costs. Incremental costs incurred to obtain parking contracts are amortized on a straight line basis over the estimated life of the contracts, including anticipated renewals and terminations. This is consistent with the timing of when the Company satisfies the related performance obligations. Estimated lives are based on the contract life or anticipated lives of the contract. The table below shows amortization expense related to cost of contracts for the three and nine months ended September 30, 2018 and 2017, respectively. Amortization expense of cost of contracts related to service concession arrangements within the scope of Topic 853 is recorded as a reduction of revenue and was not significant for the three and nine months ended September 30, 2018 and 2017, respectively. Three Months Ended Nine Months Ended (millions, unaudited) September 30, 2018 September 30, 2017 September 30, 2018 September 30, 2017 Amortization expense related to cost of contract included in depreciation and amortization $ 0.8 $ 0.8 $ 2.3 $ 2.5 As of September 30, 2018 and December 31, 2017 cost of contracts net of accumulated amortization included on the Condensed Consolidated Balance Sheets under Cost of contract, net were $8.2 million and $8.9 million , respectively. No impairment charges were recorded for the three and nine months ended September 30, 2018 and 2017, respectively.

Legal and Other Commitments and

Legal and Other Commitments and Contingencies	9 Months Ended
	Sep. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Legal and Other Commitments and Contingencies	Legal and Other Commitments and Contingencies The Company is subject to litigation in the normal course of its business. The outcomes of legal proceedings and claims brought against it and other loss contingencies are subject to significant uncertainty. The Company accrues a charge against income when its management determines that it is probable that an asset has been impaired or a liability has been incurred and the amount of loss can be reasonably estimated. In addition, the Company accrues for the authoritative judgments or assertions made against it by government agencies at the time of their rendering regardless of its intent to appeal. In addition, the Company is from time-to-time party to litigation, administrative proceedings and union grievances that arise in the normal course of business, and occasionally pays non-material amounts to resolve claims or alleged violations of regulatory requirements. There are no "normal course" matters that separately or in the aggregate, would, in the opinion of management, have a material adverse effect on its operation, financial condition or cash flow. In determining the appropriate accounting for loss contingencies, the Company considers the likelihood of loss or impairment of an asset or the incurrence of a liability, as well as its ability to reasonably estimate the amount of potential loss. The Company regularly evaluates current information available to determine whether an accrual should be established or adjusted. Estimating the probability that a loss will occur and estimating the amount of a potential loss or a range of potential loss involves significant estimation and judgment.

Restructuring, Merger and Acqui

Restructuring, Merger and Acquisition Related Costs	9 Months Ended
	Sep. 30, 2018
Business Combinations [Abstract]
Restructuring, Merger and Acquisition Related Costs	Restructuring, Merger and Acquisition Related Costs The Company incurred certain restructuring, merger and acquisition related costs through a series of separate workforce reductions and reorganizations and certain merger and acquisition related activities. These costs are expensed as incurred and reflected in General and administrative expenses within the Condensed Consolidated Statements of Income; and includes costs related to a series of Company-initiated workforce reductions and operational reorganizations in 2017 and first quarter 2018 (primarily severance and relocation costs) to increase organizational effectiveness and provide cost savings that can be reinvested in the Company's growth initiatives; and includes additional costs related to evaluating potential acquisitions during the three and nine months ended September 30, 2018 (see also Note 16. Subsequent Event ). An accrual for restructuring, merger and acquisition related costs was $2.0 million ( $1.1 million is included in Compensation and payroll withholdings, $0.5 million in Accrued Expenses and $0.4 million in Other long-term liabilities within the Condensed Consolidated Balance Sheets) and $2.3 million ( $1.8 million is included in Compensation and payroll withholdings and $0.5 million in Other long-term liabilities within the Condensed Consolidated Balance Sheets) as of September 30, 2018 and December 31, 2017, respectively. The aggregate costs associated with the restructuring, merger and acquisition related costs for the three and nine months ended September 30, 2018 and September 30, 2017 are summarized in the following table: Three Months Ended Nine Months Ended (millions) (unaudited) September 30, 2018 September 30, 2017 September 30, 2018 September 30, 2017 General and administrative expenses $ 0.6 $ — $ 3.4 $ 1.1

Other Intangible Assets, net

Other Intangible Assets, net	9 Months Ended
	Sep. 30, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Other Intangible Assets, net	Other Intangible Assets, net The following presents a summary of other intangible assets, net: September 30, 2018 (unaudited) December 31, 2017 (millions) Weighted Acquired Accumulated Acquired Acquired Accumulated Acquired Covenant not to compete 0.3 $ 0.9 $ (0.9 ) $ — $ 0.9 $ (0.9 ) $ — Trade names and trademarks 0.8 9.8 (9.7 ) 0.1 9.8 (9.7 ) 0.1 Proprietary know how 0.8 34.6 (34.6 ) — 34.6 (34.5 ) 0.1 Management contract rights 10.2 81.0 (31.0 ) 50.0 81.0 (27.1 ) 53.9 Acquired intangible assets, net (2) 10.2 $ 126.3 $ (76.2 ) $ 50.1 $ 126.3 $ (72.2 ) $ 54.1 (1) Excludes the original cost and accumulated amortization of fully amortized intangible assets. (2) Intangible assets have estimated useful lives between a half year and fourteen years . The table below shows the amortization expense related to intangible assets for the three and nine months ended September 30, 2018 and September 30, 2017: Three Months Ended Nine Months Ended (millions) (unaudited) September 30, 2018 September 30, 2017 September 30, 2018 September 30, 2017 Amortization expense related to other intangible assets included in depreciation and amortization $ 1.3 $ 1.4 $ 4.0 $ 5.9

Goodwill

Goodwill	9 Months Ended
	Sep. 30, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	Goodwill The amounts for goodwill and changes to carrying value by reportable segment are as follows: (millions) (unaudited) Region Region Total Balance as of December 31, 2017 $ 369.0 $ 62.7 $ 431.7 Foreign currency translation (0.1 ) — (0.1 ) Balance as of September 30, 2018 $ 368.9 $ 62.7 $ 431.6 The Company tests goodwill at least annually for impairment (the Company has elected to annually test for potential impairment of goodwill on the first day of the fourth quarter) and tests more frequently if indicators are present or changes in circumstances suggest that impairment may exist. The indicators include, among others, declines in sales, earnings or cash flows or the development of a material adverse change in business climate. The Company assesses goodwill for impairment at the reporting unit level, which is defined as an operating segment or one level below an operating segment, referred to as a component. The Company completed its annual goodwill impairment test as of October 1, 2017, using a qualitative test (Step Zero), to determine the likelihood of impairment and if it was more likely than not that the fair value of the reporting units were less than the carrying value of the reporting unit. The Company concluded that the estimated fair values of each of the Company's reporting units exceeded its carrying amount of net assets assigned to that reporting unit and, therefore, no further testing was required (Step One). Generally, the more-likely-than-not threshold is a greater than a 50% likelihood that the fair value of a reporting unit is greater than the carrying value. As part of the October 1, 2017 goodwill assessment, the Company engaged a third-party to estimate a discount rate, which is a primary driver in the valuation of the Company's reporting units' fair values. No impairment was recorded as a result of the goodwill impairment test performed. The Company monitors for indicators for goodwill impairment testing between annual tests. No adverse events occurred during the three and nine months ended September 30, 2018 that would cause the Company to test goodwill for impairment.

Fair Value Measurement

Fair Value Measurement	9 Months Ended
	Sep. 30, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurement	Fair Value Measurement Fair Value Measurements-Recurring Basis In determining fair value, the Company uses various valuation approaches within the fair value measurement framework. Fair value measurements are determined based on the assumptions that market participants would use in pricing an asset or liability. Applicable accounting literature establishes a hierarchy for inputs used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that the most observable inputs be used when available. The fair value hierarchy is based on observable or unobservable inputs to valuation techniques that are used to measure fair value. Observable inputs reflect assumptions market participants would use in pricing an asset or liability based on market data obtained from independent sources while unobservable inputs reflect a reporting entity’s pricing based upon its own market assumptions. Applicable accounting literature defines levels within the hierarchy based on the reliability of inputs as follows: • Level 1: Inputs are quoted prices in active markets for identical assets or liabilities. • Level 2: Inputs are quoted prices for similar assets or liabilities in an active market, quoted prices for identical or similar assets or liabilities in markets that are not active, and inputs other than quoted prices that are observable and market-corroborated inputs, which are derived principally from or corroborated by observable market data. • Level 3: Inputs that are derived from valuation techniques in which one or more significant inputs or value drivers are unobservable. As of September 30, 2018 and December 31, 2017 , the Company had no financial assets and liabilities, other than cash and cash equivalents measured at fair value on a recurring basis. The carrying value of cash and cash equivalents approximates their fair value due to the short-term nature of these financial instruments and has been classified as a Level 1. Nonrecurring Fair Value Measurements Certain assets are measured at fair value on a nonrecurring basis; that is, the assets are not measured at fair value on an ongoing basis but are subject to fair value adjustments only in certain circumstances (for example, when there is evidence of impairment). Non-financial assets such as goodwill, intangible assets, and leasehold improvements, equipment and construction in progress are subsequently measured at fair value when there is an indicator of impairment and recorded at fair value only when impairment is recognized. The Company assesses the impairment of intangible assets annually or whenever events or changes in circumstances indicate that the carrying amount of an intangible asset may not be recoverable. The fair value of its goodwill and intangible assets is not estimated if there is no change in events or circumstances that indicate the carrying amount of an intangible asset may not be recoverable. There were no impairment charges for the nine months ended September 30, 2018 and 2017 . Financial Instruments Not Measured at Fair Value The following presents the carrying amounts and estimated fair values of financial instruments not measured at fair value in the Condensed Consolidated Balance Sheets at September 30, 2018 and December 31, 2017 : September 30, 2018 (unaudited) December 31, 2017 (millions) Carrying Fair Value Carrying Fair Value Long-term borrowings Restated Credit Facility, net of original discount on borrowings and deferred financing costs $ 105.2 $ 105.2 $ 151.0 $ 151.0 Other obligations $ 2.6 $ 2.6 $ 2.8 $ 2.8 The fair value of the Restated Credit Facility and Other obligations were estimated to not be materially different from the carrying amount and are generally measured using a discounted cash flow analysis based on current market interest rates for similar types of financial instruments and would be classified as a Level 2.

Borrowing Arrangements

Borrowing Arrangements	9 Months Ended
	Sep. 30, 2018
Debt Disclosure [Abstract]
Borrowing Arrangements	Borrowing Arrangements Long-term borrowings, in order of preference, consist of: Amount Outstanding (millions) Maturity Date September 30, 2018 December 31, 2017 (unaudited) Restated Credit Facility, net of original discount on borrowings and deferred financing costs February 20, 2020 $ 105.2 $ 151.0 Other borrowings Various 2.6 2.8 Total obligations under Restated Credit Facility and other borrowings 107.8 153.8 Less: Current portion of obligations under Restated Credit Facility and other borrowings 20.9 20.6 Total long-term obligations under Restated Credit Facility and other borrowings $ 86.9 $ 133.2 Amended and Restated Credit Facility On February 20, 2015 (“Restatement Date”), the Company entered into an Amended and Restated Credit Agreement (the “Restated Credit Agreement”) with Bank of America, N.A. (“Bank of America”), as administrative agent, an issuing lender and swing-line lender; Wells Fargo Bank, N.A., as an issuing lender and syndication agent; U.S. Bank National Association, First Hawaiian Bank and BMO Harris Bank N.A., as co-documentation agents; Merrill Lynch, Pierce, Fenner & Smith Incorporated and Wells Fargo Securities, LLC, as joint lead arrangers and joint book managers; and the lenders party thereto (the “Lenders”). Pursuant to the terms, and subject to the conditions, of the Restated Credit Agreement, the Lenders have made available to the Company a senior secured credit facility (the “Restated Credit Facility”) that permits aggregate borrowings of $400.0 million consisting of (i) a revolving credit facility of up to $200.0 million at any time outstanding, which includes a $100.0 million sublimit for letters of credit and a $20.0 million sublimit for swing-line loans, and (ii) a term loan facility of $200.0 million . The Company may request increases of the revolving credit facility in an aggregate additional principal amount of $100.0 million . The Restated Credit Facility matures on February 20, 2020. The entire amount of the term loan portion of the Restated Credit Facility had been drawn by the Company as of the Restatement Date and is subject to scheduled quarterly amortization of principal as follows: (i) $15.0 million in the first year, (ii) $15.0 million in the second year, (iii) $20.0 million in the third year, (iv) $20.0 million in the fourth year, (v) $20.0 million in the fifth year and (vi) $110.0 million in the sixth year. In June 2018 and September 2018 and as allowable under the terms and conditions of the Restated Credit Facility, the Company made voluntary principal repayments of $15.0 million and $20.0 million , respectively. Debt issuance costs and original discount on borrowings written off in connection with the voluntary repayments were not significant in either period. Borrowings under the Restated Credit Facility bear interest, at the Company’s option, (i) at a rate per annum based on the Company’s consolidated total debt to EBITDA ratio for the 12 -month period ending as of the last day of the immediately preceding fiscal quarter, determined in accordance with the pricing levels set forth in the Restated Credit Agreement (the “ Applicable Margin”), plus LIBOR or (ii) the Applicable Margin plus the highest of (x) the federal funds rate plus 0.5% , (y) the Bank of America prime rate and (z) a daily rate equal to LIBOR plus 1.0% (the highest of (x), (y) and (z), the “Base Rate”), except that all swing-line loans will bear interest at the Base Rate plus the Applicable Margin. Under the terms of the Restated Credit Agreement, the Company is required to maintain a maximum consolidated total debt to EBITDA ratio of not greater than 4.0 to 1.0 as of the end of any fiscal quarter ending during the period from the Amended and Restatement Date through September 30, 2015, (ii) 3.75 to 1.0 as of the end of any fiscal quarter ending during the period from October 1, 2015 through September 30, 2016, and (iii) 3.5 to 1.0 as of the end of any fiscal quarter ending thereafter. In addition, the Company is required to maintain a minimum consolidated fixed charge coverage ratio of not less than 1.25 :1.0. Events of default under the Restated Credit Agreement include failure to pay principal or interest when due, failure to comply with the financial and operational covenants, the occurrence of any cross default event, non-compliance with the other loan documents, the occurrence of a change of control event, and bankruptcy and other insolvency events. If an event of default occurs and is continuing, the Lenders holding a majority of the commitments and outstanding term loan under the Restated Credit Agreement have the right, among others, to (i) terminate the commitments under the Restated Credit Agreement, (ii) accelerate and require the Company to repay all the outstanding amounts owed under the Restated Credit Agreement and (iii) require the Company to cash collateralize any outstanding letters of credit. Each wholly owned domestic subsidiary of the Company (subject to certain exceptions set forth in the Restated Credit Agreement) has guaranteed all existing and future indebtedness and liabilities of the other guarantors and the Company arising under the Restated Credit Agreement. The Company’s obligations under the Restated Credit Agreement and such domestic subsidiaries’ guaranty obligations are secured by substantially all of their respective assets. The Company was in compliance with all covenants as of September 30, 2018 . As of September 30, 2018 , the Company had $145.9 million of borrowing availability under the Restated Credit Agreement, of which the Company could have borrowed $145.9 million on September 30, 2018 and remained in compliance with the above described covenants as of such date. The additional borrowing availability under the Restated Credit Agreement is limited only as of the Company’s fiscal quarter-end by the covenant restrictions described above. As of September 30, 2018 , the Company had $48.1 million of letters of credit outstanding under the Restated Senior Credit Facility, with aggregate borrowings against the Restated Senior Credit Facility of $105.2 million (net of original discount on borrowings of $0.4 million and deferred financing costs of $0.5 million ).

Share Repurchase Plan

Share Repurchase Plan	9 Months Ended
	Sep. 30, 2018
Equity [Abstract]
Share Repurchase Plan	Share Repurchase Plan In May 2016, the Company's Board of Directors authorized the Company to repurchase, on the open market, shares of its outstanding common stock in an amount not to exceed $30.0 million in aggregate. Purchases of the Company's common stock may be made in open market transactions effected through a broker-dealer at prevailing market prices, in block trades, or by other means in accordance with Rules 10b-18 and 10b5-1 under the Securities Exchange Act of 1934. The share repurchase program does not obligate the Company to repurchase any particular amount of common stock, and has no fixed termination date. Under this program, the Company has repurchased 305,183 shares of common stock through September 30, 2018 at an average price of $24.43 per share, resulting in $7.5 million in program-to-date purchases. No shares were repurchased during the nine months ended September 30, 2018 and 2017.

Bradley Agreement

Bradley Agreement	9 Months Ended
	Sep. 30, 2018
Contractors [Abstract]
Bradley Agreement	Bradley Agreement The Company entered into a 25 -year agreement with the State of Connecticut (“State”) that expires on April 6, 2025, under which it operates the surface parking and 3,500 garage parking spaces at Bradley International Airport (“Bradley”) located in the Hartford, Connecticut metropolitan area. The parking garage was financed through the issuance of State of Connecticut special facility revenue bonds and provides that the Company deposits, with the trustee for the bondholders, all gross revenues collected from operations of the surface and garage parking. From these gross revenues, the trustee pays debt service on the special facility revenue bonds outstanding, operating and capital maintenance expense of the surface and garage parking facilities, and specific annual guaranteed minimum payments to the state. Principal and interest on the Bradley special facility revenue bonds increase from approximately $3.6 million in contract year 2002 to approximately $4.5 million in contract year 2025. Annual guaranteed minimum payments to the State increase from approximately $8.3 million in contract year 2002 to approximately $13.2 million in contract year 2024. The annual minimum guaranteed payment to the State by the trustee for the twelve months ended December 31, 2018 and 2017 is $11.8 million and was $11.5 million , respectively. All of the cash flow from the parking facilities are pledged to the security of the special facility revenue bonds and are collected and deposited with the bond trustee. Each month the bond trustee makes certain required monthly distributions, which are characterized as “Guaranteed Payments.” To the extent the monthly gross receipts generated by the parking facilities are not sufficient for the trustee to make the required Guaranteed Payments, the Company is obligated to deliver the deficiency amount to the trustee, with such deficiency payments representing interest bearing advances to the trustee. The Company does not directly guarantee the payment of any principal or interest on any debt obligations of the State of Connecticut or the trustee. The following is the list of Guaranteed Payments: • Garage and surface operating expenses, • Principal and interest on the special facility revenue bonds, • Trustee expenses, • Major maintenance and capital improvement deposits, and • State minimum guarantee. To the extent sufficient funds are available, the trustee is then directed to reimburse the Company for deficiency payments up to the amount of the calculated surplus, with the Company having the right to be repaid the principal amount of any and all deficiency payments, together with actual interest and premium, not to exceed 10% of the initial deficiency payment. The Company calculates and records interest and premium income along with deficiency principal repayments as a reduction of cost of parking services in the period the associated deficiency repayment is received from the trustee. The Company believes these advances to be fully recoverable as the Bradley Agreement places no time restriction on the Company’s right to reimbursement. The reimbursement of principal, interest and premium will be recognized when received. The total deficiency repayments (net of payments made) to the State as of September 30, 2018 (unaudited) are as follows: (millions) September 30, 2018 Balance as of December 31, 2017 $ 7.8 Deficiency payments made 0.1 Deficiency repayments received (3.0 ) Balance as of September 30, 2018 $ 4.9 The total deficiency repayments (net of payments made), interest and premium received and recorded for the three and nine months ended September 30, 2018 and 2017 are as follows: Three Months Ended Nine Months Ended (millions) (unaudited) September 30, 2018 September 30, 2017 September 30, 2018 September 30, 2017 Deficiency repayments $ 0.9 $ 0.5 $ 2.9 $ 1.7 Interest $ — $ — $ 0.5 $ 0.2 Premium $ 0.1 $ — $ 0.2 $ 0.2 Deficiency payments made are recorded as an increase in Cost of parking services-management type contracts and deficiency repayments, interest and premium received are recorded as reductions to Cost of parking services-management type contracts. The reimbursement of principal, interest and premium are recognized when received. There were no amounts of estimated deficiency payments accrued as of September 30, 2018 and December 31, 2017 , as the Company concluded that the potential for future deficiency payments did not meet the criteria of both probable and estimable. In addition to the recovery of certain general and administrative expenses incurred, the Bradley Agreement provides for an annual management fee payment, which is based on operating profit tiers. The annual management fee is further apportioned 60% to the Company and 40% to an un-affiliated entity and the annual management fee will be paid to the extent funds are available for the trustee to make distribution, and are paid after Guaranteed Payments (as defined in the Bradley Agreement), and after the repayment of all deficiency payments, including interest and premium. Cumulative management fees of approximately $18.5 million and $17.7 million have not been recognized as of September 30, 2018 and December 31, 2017 , respectively, and no management fees were recognized as revenue for the three and nine months ended September 30, 2018 and 2017 .

Stock-Based Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	Stock-Based Compensation Stock Grants There were 12,736 and 16,428 stock grants granted during the nine months ended September 30, 2018 and 2017 , respectively. The Company recognized $0.5 million and $0.5 million of stock-based compensation expense related to stock grants for the nine months ended September 30, 2018 and 2017 , respectively. Restricted Stock Units During the nine months ended September 30, 2018 , 52,306 restricted stock units were authorized by the Company. No restricted stock units were issued during the nine months ended September 30, 2017. During the nine months ended September 30, 2018 and 2017, 129,706 and 4,399 restricted stock units vested, respectively. During the nine months ended September 30, 2018 and 2017, 6,456 and 4,537 restricted stock units were forfeited under the Company's Long-Term Incentive Plan, as Amended and Restated (the "Plan") and became available for reissuance, respectively. The table below shows the Company's stock-based compensation expense related to the restricted stock units for the three and nine months ended September 30, 2018 and 2017 , respectively, and is included in General and administrative expenses within the Condensed Consolidated Statements of Income: Three Months Ended Nine Months Ended (millions) (unaudited) September 30, 2018 September 30, 2017 September 30, 2018 September 30, 2017 Stock-based compensation expense $ 0.3 $ 0.2 $ 0.6 $ 0.6 As of September 30, 2018 , there was $2.0 million of unrecognized stock-based compensation costs related to the restricted stock units that are expected to be recognized over a weighted average remaining period of approximately 2.4 years . Performance Share Units In September 2014, the Board of Directors authorized a performance-based incentive program under the Company’s Plan (“Performance-Based Incentive Program”), whereby the Company will issue performance share units to certain executives that represent shares potentially issuable in the future. The objective of the Performance-Based Incentive Program is to link compensation to business performance, encourage ownership of Company stock, retain executive talent, and reward executive performance. The Performance-Based Incentive Program provides participating executives with the opportunity to earn vested common stock if certain performance targets for pre-tax free cash flow are achieved over a three year performance period and recipients satisfy service-based vesting requirements. The stock-based compensation expense associated with unvested performance share units are recognized on a straight-line basis over the shorter of the vesting period or minimum service period and dependent upon the probable outcome of the number of shares that will ultimately be issued based on the achievement of pre-tax free cash flow over the cumulative three -year period. During the nine months ended September 30, 2018 and 2017, the Company granted 28,060 and 76,120 performance share units to certain executives, respectively. The grants during the nine months ended September 30, 2018 included a reduction during the quarter ending September 30, 2018 of 70,661 shares that are expected to be awarded based on the revised estimate of performance shares that are expected to vest. During the nine months ended September 30, 2018 and 2017 , 6,874 and 14,195 performance share units vested, respectively, related to certain participating executives being eligible for retirement. During the nine months ended September 30, 2018 and 2017 , 10,572 and 11,770 performance share units were forfeited under the Plan and became available for reissuance, respectively. The table below shows the Company's stock-based compensation expense (reduction of expense) related to the Performance-Based Incentive Program for the three and nine months ended September 30, 2018 and 2017 , respectively, and is included in General and administrative expenses within the Condensed Consolidated Statements of Income: Three Months Ended Nine Months Ended (millions) (unaudited) September 30, 2018 September 30, 2017 September 30, 2018 September 30, 2017 Stock-based compensation expense $ (0.4 ) $ 0.6 $ 0.7 $ 1.8 Future compensation expense for currently outstanding awards under the Performance-Based Incentive Program could reach a maximum of $12.9 million . Stock-based compensation for the Performance-Based Incentive Program is expected to be recognized over a weighted average period of 1.8 years .

Net Income per Common Share

Net Income per Common Share	9 Months Ended
	Sep. 30, 2018
Earnings Per Share [Abstract]
Net Income per Common Share	Net Income per Common Share Basic net income per share is computed by dividing net income by the weighted daily average number of shares of common stock outstanding during the period. Diluted net income per share is based upon the weighted daily average number of shares of common stock outstanding for the period plus dilutive potential common shares, including stock options and restricted stock units using the treasury-stock method. A reconciliation of the weighted average basic common shares outstanding to the weighted average diluted common shares outstanding is as follows: Three Months Ended Nine Months Ended (millions, except share and per share data) (unaudited) September 30, 2018 September 30, 2017 September 30, 2018 September 30, 2017 Net income attributable to SP Plus Corporation $ 13.5 $ 11.2 $ 44.1 $ 33.4 Basic weighted average common shares outstanding 22,439,884 22,203,023 22,370,789 22,186,556 Dilutive impact of share-based awards 186,862 320,013 236,485 314,822 Diluted weighted average common shares outstanding 22,626,746 22,523,036 22,607,274 22,501,378 Net income per common share Basic $ 0.60 $ 0.51 $ 1.97 $ 1.51 Diluted $ 0.60 $ 0.50 $ 1.95 $ 1.48 For the three and nine months ended September 30, 2018 and 2017 , unvested performance share units were excluded from the computation of weighted average diluted common share outstanding because the number of shares ultimately issuable is contingent on the Company's performance goals, which were not achieved as of the reporting date. There are no additional securities that could dilute basic earnings per share in the future that were not included in the computation of diluted earnings per share, other than those disclosed.

Comprehensive Income

Comprehensive Income	9 Months Ended
	Sep. 30, 2018
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Comprehensive Income	Comprehensive Income Comprehensive income consists of the following components, net of tax: Three Months Ended Nine Months Ended (millions) (unaudited) September 30, 2018 September 30, 2017 September 30, 2018 September 30, 2017 Net income $ 14.5 $ 12.0 $ 46.6 $ 36.0 Effective portion of unrealized loss on cash flow hedge — (0.1 ) — — Foreign currency translation 0.1 0.2 (0.4 ) 0.2 Comprehensive income 14.6 12.1 46.2 36.2 Less: Comprehensive income attributable to noncontrolling interest 1.0 0.8 2.5 2.6 Comprehensive income attributable to SP Plus Corporation $ 13.6 $ 11.3 $ 43.7 $ 33.6 Accumulated other comprehensive loss is comprised of foreign currency translation adjustments. The components of changes in accumulated comprehensive loss, net of tax, for the nine months ended September 30, 2018 were as follows: (millions) (unaudited) Foreign Currency Total Accumulated Balance as of December 31, 2017 $ (1.2 ) $ (1.2 ) Change in other comprehensive loss (0.4 ) (0.4 ) Balance as of September 30, 2018 $ (1.6 ) $ (1.6 )

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes For the three months ended September 30, 2018 , the Company recognized an income tax expense of $5.6 million on pre-tax earnings of $20.1 million , compared to $7.3 million income tax expense on pre-tax earnings of $19.3 million for the three months ended September 30, 2017 . For the nine months ended September 30, 2018 , the Company recognized an income tax expense of $16.9 million on pre-tax earnings of $63.5 million compared to $21.3 million income tax expense on pre-tax earnings of $57.3 million for the nine months ended September 30, 2017 . The effective tax rate for the nine months ended September 30, 2018 was 26.6% compared to 37.2% for the nine months ended September 30, 2017 . The effective tax rate for the nine months ended September 30, 2018 decreased primarily due to the reduction in the federal income tax rate to 21% per the 2017 Tax Act. For the year ended December 31, 2017, the Company recorded provisional estimates of the tax effects of the 2017 Tax Act in accordance with SAB 118. As of September 30, 2018, the Company has finalized its accounting for the tax effects of the 2017 Tax Act in accordance with SAB 118. During the quarter ended September 30, 2018, the Company recorded a net benefit of $1.2 million for the finalization of its transition tax liability calculation and the rate reduction for deferred tax purposes. No further adjustments under the 2017 Tax Act will be recorded. As of September 30, 2018 , the Company has not identified any uncertain tax positions that would have a material impact on the Company’s financial position. The Company recognizes potential interest and penalties related to uncertain tax positions, if any, in income tax expense. During the quarter ended September 30, 2018, the Company recognized an uncertain tax position of $0.3 million and related interest expense of $0.2 million due to an ongoing state tax examination. The tax years that remain subject to examination for the Company’s major tax jurisdictions at September 30, 2018 are shown below: 2015 – 2017 United States — federal income tax 2007 – 2017 United States — state and local income tax 2014 – 2017 Canada and Puerto Rico

Business Unit Segment Informati

Business Unit Segment Information	9 Months Ended
	Sep. 30, 2018
Segment Reporting [Abstract]
Business Unit Segment Information	Business Unit Segment Information Segment information is presented in accordance with a “management approach,” which designates the internal reporting used by the Company's Chief Operating Decision Maker (“CODM”) for making decisions and assessing performance as the source of the Company’s reportable segments. The Company’s segments are organized in a manner consistent with which discrete financial information is available and evaluated regularly by the CODM in deciding how to allocate resources and in assessing performance. An operating segment is defined as a component of an enterprise that engages in business activities from which it may earn revenue and incur expenses, and about which separate financial information is regularly evaluated by the CODM. The CODM is the Company’s chief executive officer. Each of the operating segments is directly responsible for revenue and expenses related to their operations including direct regional administrative costs. Finance, information technology, human resources, and legal are shared functions that are not allocated back to the two operating segments. The CODM assesses the performance of each operating segment using information about its revenue and gross profit as its primary measure of performance, but does not evaluate segments using discrete asset information. There are no inter-segment transactions and the Company does not allocate interest and other income, interest expense, depreciation and amortization or taxes to operating segments. The accounting policies for segment reporting are the same as for the Company as a whole. The operating segments are internally reported to the Company's CODM as Region One (Commercial) and Region Two (Airports). • Region One (Commercial) encompasses our services in healthcare facilities, municipalities, including meter revenue collection and enforcement services, government facilities, hotels, commercial real estate, residential communities, retail, colleges and universities, as well as ancillary services such as shuttle and transportation services, valet services, taxi and livery dispatch services and event planning, including shuttle and transportation services. • Region Two (Airports) encompasses our services at all major airports as well as ancillary services, which include shuttle and transportation services and valet services. • "Other" consists of ancillary revenue that is not specifically identifiable to Regions One or Two and certain unallocated items, such as and including prior year insurance reserve adjustments/costs and other corporate items. The business is managed based on regions administered by executive officers. The following is a summary of revenues (excluding reimbursed management type contract revenue) and gross profit by regions for the three and nine months ended September 30, 2018 and 2017: Three Months Ended Nine Months Ended (millions) (unaudited) September 30, 2018 Gross September 30, 2017 Gross September 30, 2018 Gross September 30, 2017 Gross Parking Services Revenue Region One Lease type contracts (1) $ 97.6 $ 108.9 $ 290.8 $ 326.0 Management type contracts 59.4 62.5 191.1 190.1 Total Region One 157.0 171.4 481.9 516.1 Region Two Lease type contracts (1) 6.9 32.0 20.3 96.6 Management type contracts 21.1 22.2 66.2 66.4 Total Region Two 28.0 54.2 86.5 163.0 Other Lease type contracts 0.2 — 0.5 — Management type contracts 2.1 2.0 7.5 6.3 Total Other 2.3 2.0 8.0 6.3 Reimbursed management type contract revenue 174.8 165.1 514.8 512.7 Total Parking Services Revenue $ 362.1 $ 392.7 $ 1,091.2 $ 1,198.1 Gross Profit Region One Lease type contracts $ 7.7 8 % $ 7.8 7 % $ 19.5 7 % $ 28.9 9 % Management type contracts 24.1 41 % 25.3 40 % 71.8 38 % 74.7 39 % Total Region One 31.8 33.1 91.3 103.6 Region Two Lease type contracts 2.0 29 % 1.6 5 % 5.6 28 % 4.9 5 % Management type contracts 6.7 32 % 6.2 28 % 20.3 31 % 19.5 29 % Total Region Two 8.7 7.8 25.9 24.4 Other Lease type contracts 0.8 400 % 0.5 — % 3.3 660 % 1.8 — % Management type contracts 3.7 176 % 4.5 225 % 15.1 201 % 14.1 224 % Total Other 4.5 5.0 18.4 15.9 Total gross profit $ 45.0 $ 45.9 $ 135.6 $ 143.9 General and administrative expenses 18.7 19.6 63.3 63.3 General and administrative expense percentage of gross profit 42 % 43 % 47 % 44 % Depreciation and amortization 4.2 4.9 12.7 16.3 Operating income 22.1 21.4 59.6 64.3 Other expenses (income) Interest expense 2.1 2.2 6.5 7.1 Interest income (0.1 ) (0.2 ) (0.3 ) (0.5 ) Gain on sale of a business — — — (0.1 ) Equity losses (earnings) from investment in unconsolidated entity — 0.1 (10.1 ) 0.5 Total other expenses (income) 2.0 2.1 (3.9 ) 7.0 Earnings before income taxes 20.1 19.3 63.5 57.3 Income tax expense 5.6 7.3 16.9 21.3 Net income 14.5 12.0 46.6 36.0 Less: Net income attributable to noncontrolling interest 1.0 0.8 2.5 2.6 Net income attributable to SP Plus Corporation $ 13.5 $ 11.2 $ 44.1 $ 33.4 (1) Includes reduction of Parking services revenue - lease type contracts due to the adoption of Topic 853, which requires rental expense for the periods after January 1, 2018 be presented as a reduction of Parking services revenue - lease type contracts for those locations (and corresponding contracts) that meet the criteria and definition of a service concession arrangement. Refer to Note 2. Revenue , for further discussion regarding the adoption of Topic 853.

Subsequent Event

Subsequent Event	9 Months Ended
	Sep. 30, 2018
Subsequent Events [Abstract]
Subsequent Event	Subsequent Event On October 16, 2018, the Company signed a definitive purchase agreement to acquire Baggage Airline Guest Services, Inc. and Home Serv Delivery, LLC, and their subsidiaries and affiliates (collectively, "Bags"), for an all cash purchase price of $275.0 million , subject to certain adjustments. Bags is a leading provider of baggage delivery, remote airline check in and other related services, primarily to airline, airport and hospitality clients. The Company plans to finance the transaction with an expanded senior credit facility. The transaction is subject to the consummation of financing, antitrust clearance and other customary closing conditions and is expected to close by the end of November 2018.

Significant Accounting Polici_2

Significant Accounting Policies and Practices (Policies)	9 Months Ended
	Sep. 30, 2018
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited Condensed Consolidated Financial Statements of the Company have been prepared in accordance with accounting principles generally accepted in the United States ("U.S. GAAP") for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, certain information and disclosures normally included in the Condensed Consolidated Balance Sheets, Statements of Income, Comprehensive Income and Cash Flows prepared in conformity with U.S. GAAP have been condensed or omitted as permitted by such rules and regulations. In the opinion of management, all adjustments (consisting only of adjustments of a normal and recurring nature) considered necessary for a fair presentation have been included. Operating results for the three and nine-month periods ended September 30, 2018 are not necessarily indicative of the results that might be expected for any other interim period or the fiscal year ending December 31, 2018 .
Cash and cash equivalents	Cash and cash equivalents Cash equivalents represent funds temporarily invested in money market instruments with maturities of three months or less. Cash equivalents are stated at cost, which approximates fair value.
Financial Instruments	Financial Instruments The carrying values of cash, accounts receivable and accounts payable approximate their fair value due to the short-term nature of these financial instruments.
Equity Investments in Unconsolidated Entities	Equity Investments in Unconsolidated Entities The Company has ownership interests in 29 active partnerships, joint ventures or similar arrangements that operate parking facilities, of which 24 are consolidated under the VIE or voting interest models and 5 are unconsolidated where the Company’s ownership interests range from 30 - 50 percent and for which there are no indicators of control. The Company accounts for such investments under the equity method of accounting, and its underlying share of each investee’s equity is included in Equity investments in unconsolidated entities within the Condensed Consolidated Balance Sheets. As the operations of these entities are consistent with the Company’s underlying core business operations, the equity in earnings of these investments are included in Parking services revenue - lease type contracts within the Condensed Consolidated Statements of Income. Included in equity earnings for the three and nine months ended September 30, 2017 are earnings of $8.5 million from the Company's proportionate share of the net gain of an equity method investees' sale of assets. The equity earnings in these related investments were $0.7 million and $0.6 million for the three months ended September 30, 2018 and 2017 , respectively, and were $1.9 million and $10.6 million for the nine months ended September 30, 2018 and 2017 , respectively. In October 2014, the Company entered into an agreement to establish a joint venture with Parkmobile USA, Inc. and contributed all of the assets and liabilities of its proprietary Click and Park parking prepayment business in exchange for a 30% interest in the newly formed legal entity called Parkmobile, LLC (“Parkmobile”). The Parkmobile joint venture combined two parking transaction engines, with SP Plus contributing the Click and Park® parking prepayment systems, which enables consumers to reserve and pay for parking online in advance and Parkmobile USA contributing its on demand transaction engine that allows consumers to transact real-time payment for parking privileges in both on- and off-street environments. On January 3, 2018, the Company closed a transaction to sell the entire 30% interest in Parkmobile to Parkmobile USA, Inc. for a gross sale price of $19.0 million and in the first quarter of 2018, the Company recognized a pre-tax gain of $10.1 million , net of closing costs, and included in Equity in losses (earnings) from investment in unconsolidated entity within the Condensed Consolidated Statements of Income for the nine months ended September 30, 2018 . The Company historically accounted for its investment in the Parkmobile joint venture using the equity method of accounting, and its underlying share of equity in Parkmobile was included in Equity investments in unconsolidated entities within the Condensed Consolidated Balance Sheets. The equity losses (earnings) in the Parkmobile joint venture were historically included in Equity in losses (earnings) from investment in unconsolidated entity within the Condensed Consolidated Statements of Income.
Noncontrolling Interests	Noncontrolling Interests Noncontrolling interests represent the noncontrolling holders’ percentage share of income or losses from the subsidiaries in which the Company holds a majority, but less than 100 percent, ownership interest and the results of which are consolidated and included within the Condensed Consolidated Financial Statements.
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements Recently Adopted Accounting Pronouncements In May 2014, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2014-09 "Revenue from Contracts with Customers" (Topic 606) and following its release, the FASB also issued the following additional ASUs updating the topic: • In December 2016, the FASB issued ASU No. 2016-20, Technical Corrections and Improvements to Topic 606, Revenue from Contracts with Customers • In May 2016, the FASB issued ASU No. 2016-12 , Revenue from Contracts with Customers (Topic 606): Narrow-Scope Improvements and Practical Expedients • In April 2016, the FASB issued ASU No. 2016-10, Revenue from Contracts with Customers (Topic 606): Identifying Performance Obligations and Licensing • In March 2016, the FASB issued ASU No. 2016-08, Revenue from Contracts with Customers (Topic 606): Principal versus Agent Considerations (Reporting Revenue Gross versus Net) • In August 2015, the FASB issued ASU No. 2015-14, Revenue from Contracts with Customers (Topic 606): Deferral of the Effective Date Topic 606 supersedes the revenue recognition requirements in ASC 605, Revenue Recognition ( Topic 605 ), and requires entities to recognize revenue when control of the promised goods or services is transferred to customers at an amount that reflects the consideration to which the entity expects to be entitled to in exchange for those goods or services. The Company adopted the provisions of Topic 606 on January 1, 2018 using the modified retrospective transition method and therefore the comparative periods have not been recasted and continue to be reported under the accounting standards in effect for those prior periods presented. The standard has been applied to contracts that have not been completed at the date of initial application. Furthermore and in accordance with Topic 606, the Company has not retrospectively restated the contracts that were modified before the beginning of the earliest reporting period presented. The aggregate effect of all modifications when identifying the satisfied and unsatisfied performance obligations were reflected in determining and allocating the transaction price. The application of these practical expedients did not have a significant impact on the Company’s financial position, results of operations, cash flows and related financial statement disclosures. In May 2017, the FASB issued ASU No. 2017-10, Service Concession Arrangements ( Topic 853 ): Determining the Customer of the Operation Services . Topic 853 further clarifies how operating entities should determine the customer of operation services for transactions within the scope of Topic 853. The Company determined that revenue generated from service concession arrangements, will be accounted for under the guidance of Topic 606 upon adoption of Topic 853. The Company adopted the provisions of Topic 853 on January 1, 2018 and upon the adoption, the Company was required to reclassify certain assets used in service concession arrangements that were previously included in Leasehold improvements, equipment and construction in progress, net, to Other assets, net within the Condensed Consolidated Balance Sheet for September 30, 2018 (as discussed previously, the prior period presented has not been recasted). In addition, the Company has the contractual right to invoice a customer prior to the performance obligation being satisfied in certain contractual arrangements, primarily related to monthly parking arrangements, and therefore effective January 1, 2018; the Company established a contract asset with a corresponding contract liability for the performance obligation expected to be satisfied at a future date. The impact of this change on the Condensed Consolidated Balance Sheet as of September 30, 2018 is as follows: Impact of Changes in Accounting Policies as of September 30, 2018 (millions, unaudited) As Reported Balances without Adoption of Topics 606 and 853 Impact of Adoption Increase/(Decrease) Assets Notes and accounts receivable, net (1) $ 136.4 $ 125.8 $ 10.6 Leasehold improvements, equipment and construction in progress, net (2) 26.3 26.8 (0.5 ) Other assets, net (2) 19.1 18.6 0.5 Liabilities Accrued expenses (1) $ 30.4 $ 19.8 $ 10.6 (1) Approximately $10.6 million and $10.6 million of contract assets and contract liabilities, respectively, were recognized as of September 30, 2018. (2) Leasehold improvements used in service concession arrangements of approximately $0.5 million were reclassified from Leasehold improvements, equipment and construction in progress to Other assets, net, as of September 30, 2018. The adoption of Topics 606 and 853 had no impact to the Company’s Operating income or Net income for the three and nine months ended September 30, 2018. Certain expenses, primarily rental expense for the contractual arrangements that meet the definition of service concession arrangements under Topic 853, have been recorded as a reduction of revenue for the three and nine months ended September 30, 2018 (as discussed above, prior periods have not been recasted). The impact of this change to gross profit and depreciation and amortization for the three and nine months ended September 30, 2018 was as follows: Impact of Changes in Accounting Policies for the Three Months Ended September 30, 2018 Impact of Changes in Accounting Policies for the Nine Months Ended September 30, 2018 (millions, unaudited) As Reported Balances without Adoption of Topics 853 and 606 Impact of Adoption As Reported Balances without Adoption of Topics 853 and 606 Impact of Adoption Increase/(Decrease) Parking services revenue Lease type contracts (1) $ 104.7 $ 138.5 $ (33.8 ) $ 311.6 $ 411.1 $ (99.5 ) Management type contracts 82.6 82.6 — 264.8 264.8 — 187.3 221.1 (33.8 ) 576.4 675.9 (99.5 ) Reimbursed management type contract revenue 174.8 174.8 — 514.8 514.8 — Total parking services revenue 362.1 395.9 (33.8 ) 1,091.2 1,190.7 (99.5 ) Cost of parking services Lease type contracts (1) 94.2 128.0 (33.8 ) 283.2 382.6 (99.4 ) Management type contracts 48.1 48.1 — 157.6 157.6 — 142.3 176.1 (33.8 ) 440.8 540.2 (99.4 ) Reimbursed management type contract expense 174.8 174.8 — 514.8 514.8 — Total cost of parking services 317.1 350.9 (33.8 ) 955.6 1,055.0 (99.4 ) Gross profit Lease type contracts 10.5 10.5 — 28.4 28.5 (0.1 ) Management type contracts 34.5 34.5 — 107.2 107.3 (0.1 ) Total gross profit $ 45.0 $ 45.0 $ — $ 135.6 $ 135.8 $ (0.2 ) Depreciation and amortization $ 4.2 $ 4.3 $ (0.1 ) $ 12.7 $ 13.0 $ (0.3 ) (1) Certain expenses, primarily rental expense for contractual arrangements that meet the definition of a service concession arrangement under Topic 853, of approximately $33.8 million and $99.4 million that would have been previously classified as Cost of parking services - lease type contracts have been classified as a reduction of revenue and included in Parking services revenue - lease type contracts for the three and nine months ended September 30, 2018, respectively. The adoption of Topics 606 and 853 did not result in a cumulative effect on our opening retained earnings and there was no impact to the Company's Condensed Consolidated Statements of Cash Flows. See Note 2. Revenue for further discussion on the impacts of adopting Topics 606 and 853. In May 2017, the FASB issued ASU No. 2017-09, Compensation - Stock Compensation (Topic 718), Scope Modification Accounting . ASU No. 2017-09 clarifies when to account for a change to the terms or conditions of a share-based payment award as a modification. Under the new guidance, modification accounting is required only if the fair value, the vesting conditions, or the classification of the award (as equity or liability) changes as a result of the change in terms or conditions. The guidance is effective prospectively for all companies for annual periods beginning on or after December 15, 2017. Early adoption is permitted. The Company adopted the standard as of January 1, 2018. The standard did not have an impact on the Company’s financial position, results of operations, cash flows and financial statement disclosures. In January 2017, the FASB issued ASU No. 2017-01, Business Combinations - Clarifying the Definition of a Business (Topic 805) . Under ASU No. 2017-01, an entity first determines whether substantially all of the fair value of the gross assets acquired is concentrated in a single identifiable asset or a group of similar identifiable assets. If this threshold is met, the set is not a business. If it’s not met, the entity then evaluates whether the set meets the requirement that a business include, at a minimum, an input and a substantive process that together significantly contribute to the ability to create outputs. Under current guidance, a business consists of (1) inputs, (2) processes applied to those inputs and (3) the ability to create outputs. ASU No. 2017-01 is effective for fiscal years beginning after December 15, 2017, and interim periods within those years. The standard will be applied prospectively to any transactions occurring within the period of adoption. The Company adopted the standard as of January 1, 2018. The standard did not have an impact on the Company’s financial position, results of operations, cash flows and financial statement disclosures. In November 2016, the FASB issued ASU No. 2016-18, Statement of Cash Flows - Restricted Cash (Topic 230) . ASU No. 2016-18 clarifies how entities should present restricted cash and restricted cash equivalents in the statement of cash flows. The guidance requires entities to show the changes in the total of cash, cash equivalents, restricted cash and restricted cash equivalents in the statement of cash flows. As a result, entities will no longer present transfers between cash and cash equivalents and restricted cash and restricted cash equivalents in the statement of cash flows. The guidance, which is based on a consensus of the Emerging Issues Task Force (EITF), is effective for fiscal years beginning after December 15, 2017, and interim periods within those years. The Company adopted this standard as of January 1, 2018. The standard did not have an impact on the Company's financial position, results of operation, cash flows and financial statement disclosures. In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows - Classification of Certain Cash Receipts and Cash Payments (Topic 230) . ASU 2016-15 amends the guidance in ASC 230 related to the classification of certain cash receipts and payments in the statement of cash flows. The primary purpose of the ASU is to reduce the diversity in practice that has resulted from the lack of consistent principles on this topic. The amendment adds or clarifies several statement of cash flow classification issues including: (i) debt prepayment or debt extinguishment costs, (ii) settlement of certain zero-coupon debt instruments, (iii) contingent consideration payments, (iv) proceeds from the settlement of insurance claims, (v) proceeds from the settlement of corporate-owned life insurance policies, (vi) distributions received from equity method investments, (vii) beneficial interest in securitization transactions, and (viii) separately identifiable cash flows and application of the predominance principle. The standard is effective for interim and annual reporting periods beginning after December 15, 2017. The Company adopted this standard as of January 1, 2018. The standard did not have an impact on the Company's financial position, results of operation, cash flows and financial statement disclosures. In January 2016, the FASB issued ASU No. 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities . ASU No. 2016-01 amends various areas of the accounting for financial instruments. Key provisions of the amendment require (i) equity investments to be measured at fair value (except those accounted for under the equity method), (ii) the simplification of equity investment impairment determination, (iii) certain changes to the fair value measurement of financial instruments measured at amortized cost, (iv) the separate presentation, in other comprehensive income, the portion of the total change in the fair value of the liability resulting from a change in the instrument-specific credit risk (given certain conditions), and (v) the evaluation for a valuation allowance on a deferred tax asset related to available-for-sale securities in combination with the Company's other deferred tax assets. ASU No. 2016-01 is effective for interim and annual reporting periods beginning after December 15, 2017. The Company adopted this standard as of January 1, 2018. The standard did not have an impact on the Company's financial position, results of operation, cash flows and financial statement disclosures. Accounting Pronouncements to be Adopted In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842). ASU No. 2016-02 requires lessees to record most leases on the balance sheet and recognize expense, similar to current accounting guidance, on the income statement. Additionally, the classification criteria and the accounting for sales-type and direct financing leases is modified for lessors. Under ASU No. 2016-02, all entities are required to recognize "right-of-use" ("ROU") assets and lease liabilities on the balance sheet for all leases classified as either operating or finance leases. Lease classification will determine recognition of lease-related revenue and expense. Since the release of ASU No. 2016-02, the FASB also issued the following additional ASUs updating the topic: • In January 2018, the FASB issued ASU No. 2018-01, Land Easement Practical Expedient for Transition to Topic 842 • In July 2018, the FASB issued ASU No. 2018-11, Lease (Topic 842): Targeted Improvements • In July 2018, the FASB issued ASU No. 2018-10, Codification Improvements to Topic 842, Leases ASU No. 2016-02 and its related ASUs are effective for interim and annual reporting periods beginning after December 15, 2018. The Company has commenced the process of implementing Topic 842 and has developed a project plan to guide the implementation and assessment of the impact of the standard and other changes to the Company's financial position, results of operations, cash flows and financial statement disclosures. The Company has made progress on this project plan including assessing the Company’s portfolio of leases, understanding key policy elections and considerations under the standard as well as changes to key processes and internal controls. The Company has selected a lease accounting software solution to support the new reporting requirements and has commenced the process of extracting lease data from lease agreements for input into the software solution. The Company will take advantage of the transition package of practical expedients as permitted within ASU No. 2016-02 which among other things allows the Company to carry forward the historical lease classification. The Company will be making an accounting policy election to keep leases with an initial lease term of 12 months or less off of the Consolidated Balance Sheet and therefore there will be no requirement to recognize ROU assets and lease liabilities for these leases. While the Company continues to assess the potential impacts of the new standard, the most significant impact upon adoption will be the recognition of ROU assets and lease liabilities for operating leases. However, the Company does not expect adoption will have a material impact on the Consolidated Statement of Income. The Company expects the accounting for capital leases to remain substantially unchanged. In June 2018, the FASB issued ASU No. 2018-07, Compensation—Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting . Under existing guidance, the accounting for nonemployee share-based payments differs from that applied to employee awards, particularly with regard to the measurement date and the impact of performance conditions. This ASU provides for existing employee guidance will apply to nonemployee share-based transactions (as long as the transaction is not effectively a form of financing), with the exception of specific guidance related to the attribution of compensation cost. The cost of nonemployee awards will continue to be recorded as if the grantor had paid cash for the goods or services. In addition, the contractual term will be able to be used in lieu of an expected term in the option-pricing model for nonemployee awards. ASU No. 2018-07 is effective for all companies for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years. Public business entities may early adopt the guidance for financial statements that have not yet been issued but no earlier than an entity’s adoption date of Topic 606. The Company is currently assessing the impact of adopting the standard on the Company's financial position, results of operations, cash flows and financial statement disclosures. In February 2018, the FASB issued ASU No. 2018-02, Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income . The ASU provides guidance that permits companies to reclassify disproportionate tax effects in accumulated other comprehensive income (AOCI) caused by the Tax Cuts and Jobs Act of 2017 (the "2017 Tax Act") to retained earnings. The FASB refers to these amounts as "stranded tax effects." Companies that elect to reclassify the effects associated with the change in US federal corporate income tax rate must do so for all items within the AOCI. The new guidance also requires all companies to include certain new disclosures in their financial statements, regardless of whether a company opts to make the reclassification. Companies may adopt the new guidance using one of two transition methods: (1) retrospective to each period (or periods) in which the income tax effects of the 2017 Tax Act related to items remaining in AOCI are recognized, or (2) at the beginning of the period of adoption. ASU No. 2018-02 is effective for all companies for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years. Public business entities may early adopt the guidance for financial statements that have not yet been issued. The Company is currently assessing the impact of adopting the standard on the Company's financial position, results of operations, cash flows and financial statement disclosures. In January 2017, the FASB issued ASU No. 2017-04, Intangibles – Goodwill and Other (Topic 350): Simplifying the Accounting for Goodwill Impairment. The new guidance simplifies the accounting for goodwill impairment by removing Step 2 of the goodwill impairment test, which requires a hypothetical purchase price allocation. A goodwill impairment will now be the amount by which a reporting unit’s carrying value exceeds its fair value, not to exceed the carrying amount of goodwill. All other goodwill impairment guidance will remain largely unchanged. Entities will continue to have the option to perform a qualitative assessment to determine if a quantitative impairment test is necessary. The same one-step impairment test will be applied to goodwill at all reporting units, even those with zero or negative carrying amounts. Entities will be required to disclose the amount of goodwill at reporting units with zero or negative carrying amounts. ASU No. 2017-04 is effective for annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2019. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The Company is currently assessing the impact of adopting the standard on the Company's financial position, results of operations, cash flows and financial statement disclosures. In June 2016, the FASB issued ASU No. 2016-13, Credit Losses - Measurement of Credit Losses on Financial Instruments (Topic 326) . The standard significantly changes how entities will measure credit losses for most financial assets and certain other instruments that are not measured at fair value through net income. The standard will replace today’s “incurred loss” approach with an “expected loss” model for instruments measured at amortized cost. For available-for-sale debt securities, entities will be required to record allowances rather than reduce the carrying amount, as they do today under the other-than-temporary impairment model. Entities will apply the standard’s provisions as a cumulative-effect adjustment to retained earnings as of the beginning of the first reporting period in which the guidance is effective. The standard is effective for interim and annual reporting periods beginning after December 15, 2019. The Company is currently assessing the impact of adopting this standard on the Company’s financial position, results of operations, cash flows and financial statement disclosures. In August 2018, the FASB issued ASU No. 2018-15, Intangibles – Goodwill and Other – Internal - Use Software (Subtopic 350-40): Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract. The standard requires a customer in a cloud computing arrangement that is a service contract to follow the internal-use software guidance in Accounting Standards Codification (ASC) 350-40 to determine which implementation costs to capitalize as assets. Capitalized implementation costs related to a hosting arrangement that is a service contract will be amortized over the term of the hosting arrangement, beginning when the module or component of the hosting arrangement is ready for its intended use. The standard is effective for interim and annual reporting periods beginning after December 15, 2019. The Company is currently assessing the impact of adopting this standard on the Company’s financial position, results of operations, cash flows and financial statement disclosures. In August 2018, the FASB issued ASU No. 2018-13, Fair Value Measurement (Topic 820). This standard modifies the disclosures on fair value measurements by removing the requirement to disclose the amount and reasons for transfers between Level 1 and Level 2 of the fair value hierarchy and the policy for timing of such transfers. The ASU expands the disclosure requirements for Level 3 fair value measurements, primarily focused on changes in unrealized gains and losses included in other comprehensive income. The standard is effective for interim and annual reporting periods beginning after December 15, 2019. The Company is currently assessing the impact of adopting this standard on the Company’s financial position, results of operations, cash flows and financial statement disclosures.

Significant Accounting Polici_3

Significant Accounting Policies and Practices (Tables)	9 Months Ended
	Sep. 30, 2018
Accounting Policies [Abstract]
Schedule of Contract with Customer, Asset and Liability	The Company adopted the provisions of Topic 853 on January 1, 2018 and upon the adoption, the Company was required to reclassify certain assets used in service concession arrangements that were previously included in Leasehold improvements, equipment and construction in progress, net, to Other assets, net within the Condensed Consolidated Balance Sheet for September 30, 2018 (as discussed previously, the prior period presented has not been recasted). In addition, the Company has the contractual right to invoice a customer prior to the performance obligation being satisfied in certain contractual arrangements, primarily related to monthly parking arrangements, and therefore effective January 1, 2018; the Company established a contract asset with a corresponding contract liability for the performance obligation expected to be satisfied at a future date. The impact of this change on the Condensed Consolidated Balance Sheet as of September 30, 2018 is as follows: Impact of Changes in Accounting Policies as of September 30, 2018 (millions, unaudited) As Reported Balances without Adoption of Topics 606 and 853 Impact of Adoption Increase/(Decrease) Assets Notes and accounts receivable, net (1) $ 136.4 $ 125.8 $ 10.6 Leasehold improvements, equipment and construction in progress, net (2) 26.3 26.8 (0.5 ) Other assets, net (2) 19.1 18.6 0.5 Liabilities Accrued expenses (1) $ 30.4 $ 19.8 $ 10.6 (1) Approximately $10.6 million and $10.6 million of contract assets and contract liabilities, respectively, were recognized as of September 30, 2018. (2) Leasehold improvements used in service concession arrangements of approximately $0.5 million were reclassified from Leasehold improvements, equipment and construction in progress to Other assets, net, as of September 30, 2018. The following table provides information about contract assets and contract liabilities with customers and clients as of September 30, 2018: (millions, unaudited) September 30, 2018 Accounts receivable $ 125.6 Contract asset $ 10.8 Contract liability $ (16.5 ) The following table provides information about changes to contract liability balances for the nine-month period ended September 30, 2018: (millions, unaudited) Contract Liability Balance as of January 1, 2018 $ (20.5 ) Additional contract liabilities (128.6 ) Recognition of revenue from contract liabilities 132.6 Balance as of September 30, 2018 $ (16.5 ) The following table provides information about changes to contract asset balances for the nine-month period ended September 30, 2018: (millions, unaudited) Contract Asset Balance as of January 1, 2018 $ 12.2 Additional contract assets 100.0 Reclassification to accounts receivable (101.4 ) Balance as of September 30, 2018 $ 10.8
Schedule of Disaggregation of Revenue	The adoption of Topics 606 and 853 had no impact to the Company’s Operating income or Net income for the three and nine months ended September 30, 2018. Certain expenses, primarily rental expense for the contractual arrangements that meet the definition of service concession arrangements under Topic 853, have been recorded as a reduction of revenue for the three and nine months ended September 30, 2018 (as discussed above, prior periods have not been recasted). The impact of this change to gross profit and depreciation and amortization for the three and nine months ended September 30, 2018 was as follows: Impact of Changes in Accounting Policies for the Three Months Ended September 30, 2018 Impact of Changes in Accounting Policies for the Nine Months Ended September 30, 2018 (millions, unaudited) As Reported Balances without Adoption of Topics 853 and 606 Impact of Adoption As Reported Balances without Adoption of Topics 853 and 606 Impact of Adoption Increase/(Decrease) Parking services revenue Lease type contracts (1) $ 104.7 $ 138.5 $ (33.8 ) $ 311.6 $ 411.1 $ (99.5 ) Management type contracts 82.6 82.6 — 264.8 264.8 — 187.3 221.1 (33.8 ) 576.4 675.9 (99.5 ) Reimbursed management type contract revenue 174.8 174.8 — 514.8 514.8 — Total parking services revenue 362.1 395.9 (33.8 ) 1,091.2 1,190.7 (99.5 ) Cost of parking services Lease type contracts (1) 94.2 128.0 (33.8 ) 283.2 382.6 (99.4 ) Management type contracts 48.1 48.1 — 157.6 157.6 — 142.3 176.1 (33.8 ) 440.8 540.2 (99.4 ) Reimbursed management type contract expense 174.8 174.8 — 514.8 514.8 — Total cost of parking services 317.1 350.9 (33.8 ) 955.6 1,055.0 (99.4 ) Gross profit Lease type contracts 10.5 10.5 — 28.4 28.5 (0.1 ) Management type contracts 34.5 34.5 — 107.2 107.3 (0.1 ) Total gross profit $ 45.0 $ 45.0 $ — $ 135.6 $ 135.8 $ (0.2 ) Depreciation and amortization $ 4.2 $ 4.3 $ (0.1 ) $ 12.7 $ 13.0 $ (0.3 ) (1) Certain expenses, primarily rental expense for contractual arrangements that meet the definition of a service concession arrangement under Topic 853, of approximately $33.8 million and $99.4 million that would have been previously classified as Cost of parking services - lease type contracts have been classified as a reduction of revenue and included in Parking services revenue - lease type contracts for the three and nine months ended September 30, 2018, respectively. The table below shows amortization expense related to cost of contracts for the three and nine months ended September 30, 2018 and 2017, respectively. Amortization expense of cost of contracts related to service concession arrangements within the scope of Topic 853 is recorded as a reduction of revenue and was not significant for the three and nine months ended September 30, 2018 and 2017, respectively. Three Months Ended Nine Months Ended (millions, unaudited) September 30, 2018 September 30, 2017 September 30, 2018 September 30, 2017 Amortization expense related to cost of contract included in depreciation and amortization $ 0.8 $ 0.8 $ 2.3 $ 2.5

Revenue (Tables)

Revenue (Tables)	9 Months Ended
	Sep. 30, 2018
Revenue from Contract with Customer [Abstract]
Schedule of Remaining Performance Obligation	The Company expects to recognize our remaining performance obligations as revenue in future periods as follows: (millions, unaudited) Remaining Performance Obligations 2018 $ 13.1 2019 38.3 2020 24.9 2021 12.8 2022 8.0 2023 and thereafter 9.6 Total $ 106.7
Schedule of Contract with Customer, Asset and Liability	The Company adopted the provisions of Topic 853 on January 1, 2018 and upon the adoption, the Company was required to reclassify certain assets used in service concession arrangements that were previously included in Leasehold improvements, equipment and construction in progress, net, to Other assets, net within the Condensed Consolidated Balance Sheet for September 30, 2018 (as discussed previously, the prior period presented has not been recasted). In addition, the Company has the contractual right to invoice a customer prior to the performance obligation being satisfied in certain contractual arrangements, primarily related to monthly parking arrangements, and therefore effective January 1, 2018; the Company established a contract asset with a corresponding contract liability for the performance obligation expected to be satisfied at a future date. The impact of this change on the Condensed Consolidated Balance Sheet as of September 30, 2018 is as follows: Impact of Changes in Accounting Policies as of September 30, 2018 (millions, unaudited) As Reported Balances without Adoption of Topics 606 and 853 Impact of Adoption Increase/(Decrease) Assets Notes and accounts receivable, net (1) $ 136.4 $ 125.8 $ 10.6 Leasehold improvements, equipment and construction in progress, net (2) 26.3 26.8 (0.5 ) Other assets, net (2) 19.1 18.6 0.5 Liabilities Accrued expenses (1) $ 30.4 $ 19.8 $ 10.6 (1) Approximately $10.6 million and $10.6 million of contract assets and contract liabilities, respectively, were recognized as of September 30, 2018. (2) Leasehold improvements used in service concession arrangements of approximately $0.5 million were reclassified from Leasehold improvements, equipment and construction in progress to Other assets, net, as of September 30, 2018. The following table provides information about contract assets and contract liabilities with customers and clients as of September 30, 2018: (millions, unaudited) September 30, 2018 Accounts receivable $ 125.6 Contract asset $ 10.8 Contract liability $ (16.5 ) The following table provides information about changes to contract liability balances for the nine-month period ended September 30, 2018: (millions, unaudited) Contract Liability Balance as of January 1, 2018 $ (20.5 ) Additional contract liabilities (128.6 ) Recognition of revenue from contract liabilities 132.6 Balance as of September 30, 2018 $ (16.5 ) The following table provides information about changes to contract asset balances for the nine-month period ended September 30, 2018: (millions, unaudited) Contract Asset Balance as of January 1, 2018 $ 12.2 Additional contract assets 100.0 Reclassification to accounts receivable (101.4 ) Balance as of September 30, 2018 $ 10.8
Schedule of Amortization Expense Related to Cost of Contracts	The adoption of Topics 606 and 853 had no impact to the Company’s Operating income or Net income for the three and nine months ended September 30, 2018. Certain expenses, primarily rental expense for the contractual arrangements that meet the definition of service concession arrangements under Topic 853, have been recorded as a reduction of revenue for the three and nine months ended September 30, 2018 (as discussed above, prior periods have not been recasted). The impact of this change to gross profit and depreciation and amortization for the three and nine months ended September 30, 2018 was as follows: Impact of Changes in Accounting Policies for the Three Months Ended September 30, 2018 Impact of Changes in Accounting Policies for the Nine Months Ended September 30, 2018 (millions, unaudited) As Reported Balances without Adoption of Topics 853 and 606 Impact of Adoption As Reported Balances without Adoption of Topics 853 and 606 Impact of Adoption Increase/(Decrease) Parking services revenue Lease type contracts (1) $ 104.7 $ 138.5 $ (33.8 ) $ 311.6 $ 411.1 $ (99.5 ) Management type contracts 82.6 82.6 — 264.8 264.8 — 187.3 221.1 (33.8 ) 576.4 675.9 (99.5 ) Reimbursed management type contract revenue 174.8 174.8 — 514.8 514.8 — Total parking services revenue 362.1 395.9 (33.8 ) 1,091.2 1,190.7 (99.5 ) Cost of parking services Lease type contracts (1) 94.2 128.0 (33.8 ) 283.2 382.6 (99.4 ) Management type contracts 48.1 48.1 — 157.6 157.6 — 142.3 176.1 (33.8 ) 440.8 540.2 (99.4 ) Reimbursed management type contract expense 174.8 174.8 — 514.8 514.8 — Total cost of parking services 317.1 350.9 (33.8 ) 955.6 1,055.0 (99.4 ) Gross profit Lease type contracts 10.5 10.5 — 28.4 28.5 (0.1 ) Management type contracts 34.5 34.5 — 107.2 107.3 (0.1 ) Total gross profit $ 45.0 $ 45.0 $ — $ 135.6 $ 135.8 $ (0.2 ) Depreciation and amortization $ 4.2 $ 4.3 $ (0.1 ) $ 12.7 $ 13.0 $ (0.3 ) (1) Certain expenses, primarily rental expense for contractual arrangements that meet the definition of a service concession arrangement under Topic 853, of approximately $33.8 million and $99.4 million that would have been previously classified as Cost of parking services - lease type contracts have been classified as a reduction of revenue and included in Parking services revenue - lease type contracts for the three and nine months ended September 30, 2018, respectively. The table below shows amortization expense related to cost of contracts for the three and nine months ended September 30, 2018 and 2017, respectively. Amortization expense of cost of contracts related to service concession arrangements within the scope of Topic 853 is recorded as a reduction of revenue and was not significant for the three and nine months ended September 30, 2018 and 2017, respectively. Three Months Ended Nine Months Ended (millions, unaudited) September 30, 2018 September 30, 2017 September 30, 2018 September 30, 2017 Amortization expense related to cost of contract included in depreciation and amortization $ 0.8 $ 0.8 $ 2.3 $ 2.5

Restructuring, Merger and Acq_2

Restructuring, Merger and Acquisition Related Costs (Tables)	9 Months Ended
	Sep. 30, 2018
Business Combinations [Abstract]
Schedule of Acquisition Related Costs	The aggregate costs associated with the restructuring, merger and acquisition related costs for the three and nine months ended September 30, 2018 and September 30, 2017 are summarized in the following table: Three Months Ended Nine Months Ended (millions) (unaudited) September 30, 2018 September 30, 2017 September 30, 2018 September 30, 2017 General and administrative expenses $ 0.6 $ — $ 3.4 $ 1.1

Other Intangible Assets, net (T

Other Intangible Assets, net (Tables)	9 Months Ended
	Sep. 30, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Summary of Intangible Assets, Net	The following presents a summary of other intangible assets, net: September 30, 2018 (unaudited) December 31, 2017 (millions) Weighted Acquired Accumulated Acquired Acquired Accumulated Acquired Covenant not to compete 0.3 $ 0.9 $ (0.9 ) $ — $ 0.9 $ (0.9 ) $ — Trade names and trademarks 0.8 9.8 (9.7 ) 0.1 9.8 (9.7 ) 0.1 Proprietary know how 0.8 34.6 (34.6 ) — 34.6 (34.5 ) 0.1 Management contract rights 10.2 81.0 (31.0 ) 50.0 81.0 (27.1 ) 53.9 Acquired intangible assets, net (2) 10.2 $ 126.3 $ (76.2 ) $ 50.1 $ 126.3 $ (72.2 ) $ 54.1 (1) Excludes the original cost and accumulated amortization of fully amortized intangible assets. (2) Intangible assets have estimated useful lives between a half year and fourteen years .
Summary of Amortization of Intangible Assets	The table below shows the amortization expense related to intangible assets for the three and nine months ended September 30, 2018 and September 30, 2017: Three Months Ended Nine Months Ended (millions) (unaudited) September 30, 2018 September 30, 2017 September 30, 2018 September 30, 2017 Amortization expense related to other intangible assets included in depreciation and amortization $ 1.3 $ 1.4 $ 4.0 $ 5.9

Goodwill (Tables)

Goodwill (Tables)	9 Months Ended
	Sep. 30, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Amounts for Goodwill and Changes to Carrying Value by Operating Segment	The amounts for goodwill and changes to carrying value by reportable segment are as follows: (millions) (unaudited) Region Region Total Balance as of December 31, 2017 $ 369.0 $ 62.7 $ 431.7 Foreign currency translation (0.1 ) — (0.1 ) Balance as of September 30, 2018 $ 368.9 $ 62.7 $ 431.6

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	9 Months Ended
	Sep. 30, 2018
Fair Value Disclosures [Abstract]
Schedule of Carrying Amount and Estimated Fair Values	The following presents the carrying amounts and estimated fair values of financial instruments not measured at fair value in the Condensed Consolidated Balance Sheets at September 30, 2018 and December 31, 2017 : September 30, 2018 (unaudited) December 31, 2017 (millions) Carrying Fair Value Carrying Fair Value Long-term borrowings Restated Credit Facility, net of original discount on borrowings and deferred financing costs $ 105.2 $ 105.2 $ 151.0 $ 151.0 Other obligations $ 2.6 $ 2.6 $ 2.8 $ 2.8

Borrowing Arrangements (Tables)

Borrowing Arrangements (Tables)	9 Months Ended
	Sep. 30, 2018
Debt Disclosure [Abstract]
Schedule of Long-term Borrowings	Long-term borrowings, in order of preference, consist of: Amount Outstanding (millions) Maturity Date September 30, 2018 December 31, 2017 (unaudited) Restated Credit Facility, net of original discount on borrowings and deferred financing costs February 20, 2020 $ 105.2 $ 151.0 Other borrowings Various 2.6 2.8 Total obligations under Restated Credit Facility and other borrowings 107.8 153.8 Less: Current portion of obligations under Restated Credit Facility and other borrowings 20.9 20.6 Total long-term obligations under Restated Credit Facility and other borrowings $ 86.9 $ 133.2

Bradley Agreement (Tables)

Bradley Agreement (Tables)	9 Months Ended
	Sep. 30, 2018
Contractors [Abstract]
Schedule of Deficiency Payments Made, Net of Reimbursements	The total deficiency repayments (net of payments made), interest and premium received and recorded for the three and nine months ended September 30, 2018 and 2017 are as follows: Three Months Ended Nine Months Ended (millions) (unaudited) September 30, 2018 September 30, 2017 September 30, 2018 September 30, 2017 Deficiency repayments $ 0.9 $ 0.5 $ 2.9 $ 1.7 Interest $ — $ — $ 0.5 $ 0.2 Premium $ 0.1 $ — $ 0.2 $ 0.2 The total deficiency repayments (net of payments made) to the State as of September 30, 2018 (unaudited) are as follows: (millions) September 30, 2018 Balance as of December 31, 2017 $ 7.8 Deficiency payments made 0.1 Deficiency repayments received (3.0 ) Balance as of September 30, 2018 $ 4.9

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Stock-Based Compensation Expense	The table below shows the Company's stock-based compensation expense related to the restricted stock units for the three and nine months ended September 30, 2018 and 2017 , respectively, and is included in General and administrative expenses within the Condensed Consolidated Statements of Income: Three Months Ended Nine Months Ended (millions) (unaudited) September 30, 2018 September 30, 2017 September 30, 2018 September 30, 2017 Stock-based compensation expense $ 0.3 $ 0.2 $ 0.6 $ 0.6 The table below shows the Company's stock-based compensation expense (reduction of expense) related to the Performance-Based Incentive Program for the three and nine months ended September 30, 2018 and 2017 , respectively, and is included in General and administrative expenses within the Condensed Consolidated Statements of Income: Three Months Ended Nine Months Ended (millions) (unaudited) September 30, 2018 September 30, 2017 September 30, 2018 September 30, 2017 Stock-based compensation expense $ (0.4 ) $ 0.6 $ 0.7 $ 1.8

Net Income per Common Share (Ta

Net Income per Common Share (Tables)	9 Months Ended
	Sep. 30, 2018
Earnings Per Share [Abstract]
Schedule of Reconciliation of Weighted Average Shares	A reconciliation of the weighted average basic common shares outstanding to the weighted average diluted common shares outstanding is as follows: Three Months Ended Nine Months Ended (millions, except share and per share data) (unaudited) September 30, 2018 September 30, 2017 September 30, 2018 September 30, 2017 Net income attributable to SP Plus Corporation $ 13.5 $ 11.2 $ 44.1 $ 33.4 Basic weighted average common shares outstanding 22,439,884 22,203,023 22,370,789 22,186,556 Dilutive impact of share-based awards 186,862 320,013 236,485 314,822 Diluted weighted average common shares outstanding 22,626,746 22,523,036 22,607,274 22,501,378 Net income per common share Basic $ 0.60 $ 0.51 $ 1.97 $ 1.51 Diluted $ 0.60 $ 0.50 $ 1.95 $ 1.48

Comprehensive Income (Tables)

Comprehensive Income (Tables)	9 Months Ended
	Sep. 30, 2018
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Schedule of Components of Comprehensive Income, Net of Tax	Comprehensive income consists of the following components, net of tax: Three Months Ended Nine Months Ended (millions) (unaudited) September 30, 2018 September 30, 2017 September 30, 2018 September 30, 2017 Net income $ 14.5 $ 12.0 $ 46.6 $ 36.0 Effective portion of unrealized loss on cash flow hedge — (0.1 ) — — Foreign currency translation 0.1 0.2 (0.4 ) 0.2 Comprehensive income 14.6 12.1 46.2 36.2 Less: Comprehensive income attributable to noncontrolling interest 1.0 0.8 2.5 2.6 Comprehensive income attributable to SP Plus Corporation $ 13.6 $ 11.3 $ 43.7 $ 33.6
Components of Accumulated Comprehensive Income (Loss), Net of Tax	The components of changes in accumulated comprehensive loss, net of tax, for the nine months ended September 30, 2018 were as follows: (millions) (unaudited) Foreign Currency Total Accumulated Balance as of December 31, 2017 $ (1.2 ) $ (1.2 ) Change in other comprehensive loss (0.4 ) (0.4 ) Balance as of September 30, 2018 $ (1.6 ) $ (1.6 )

Business Unit Segment Informa_2

Business Unit Segment Information (Tables)	9 Months Ended
	Sep. 30, 2018
Segment Reporting [Abstract]
Summary of Revenues and Gross Profit by Regions	The following is a summary of revenues (excluding reimbursed management type contract revenue) and gross profit by regions for the three and nine months ended September 30, 2018 and 2017: Three Months Ended Nine Months Ended (millions) (unaudited) September 30, 2018 Gross September 30, 2017 Gross September 30, 2018 Gross September 30, 2017 Gross Parking Services Revenue Region One Lease type contracts (1) $ 97.6 $ 108.9 $ 290.8 $ 326.0 Management type contracts 59.4 62.5 191.1 190.1 Total Region One 157.0 171.4 481.9 516.1 Region Two Lease type contracts (1) 6.9 32.0 20.3 96.6 Management type contracts 21.1 22.2 66.2 66.4 Total Region Two 28.0 54.2 86.5 163.0 Other Lease type contracts 0.2 — 0.5 — Management type contracts 2.1 2.0 7.5 6.3 Total Other 2.3 2.0 8.0 6.3 Reimbursed management type contract revenue 174.8 165.1 514.8 512.7 Total Parking Services Revenue $ 362.1 $ 392.7 $ 1,091.2 $ 1,198.1 Gross Profit Region One Lease type contracts $ 7.7 8 % $ 7.8 7 % $ 19.5 7 % $ 28.9 9 % Management type contracts 24.1 41 % 25.3 40 % 71.8 38 % 74.7 39 % Total Region One 31.8 33.1 91.3 103.6 Region Two Lease type contracts 2.0 29 % 1.6 5 % 5.6 28 % 4.9 5 % Management type contracts 6.7 32 % 6.2 28 % 20.3 31 % 19.5 29 % Total Region Two 8.7 7.8 25.9 24.4 Other Lease type contracts 0.8 400 % 0.5 — % 3.3 660 % 1.8 — % Management type contracts 3.7 176 % 4.5 225 % 15.1 201 % 14.1 224 % Total Other 4.5 5.0 18.4 15.9 Total gross profit $ 45.0 $ 45.9 $ 135.6 $ 143.9 General and administrative expenses 18.7 19.6 63.3 63.3 General and administrative expense percentage of gross profit 42 % 43 % 47 % 44 % Depreciation and amortization 4.2 4.9 12.7 16.3 Operating income 22.1 21.4 59.6 64.3 Other expenses (income) Interest expense 2.1 2.2 6.5 7.1 Interest income (0.1 ) (0.2 ) (0.3 ) (0.5 ) Gain on sale of a business — — — (0.1 ) Equity losses (earnings) from investment in unconsolidated entity — 0.1 (10.1 ) 0.5 Total other expenses (income) 2.0 2.1 (3.9 ) 7.0 Earnings before income taxes 20.1 19.3 63.5 57.3 Income tax expense 5.6 7.3 16.9 21.3 Net income 14.5 12.0 46.6 36.0 Less: Net income attributable to noncontrolling interest 1.0 0.8 2.5 2.6 Net income attributable to SP Plus Corporation $ 13.5 $ 11.2 $ 44.1 $ 33.4 (1) Includes reduction of Parking services revenue - lease type contracts due to the adoption of Topic 853, which requires rental expense for the periods after January 1, 2018 be presented as a reduction of Parking services revenue - lease type contracts for those locations (and corresponding contracts) that meet the criteria and definition of a service concession arrangement. Refer to Note 2. Revenue , for further discussion regarding the adoption of Topic 853.

Significant Accounting Polici_4

Significant Accounting Policies and Practices - Narrative (Details) $ in Millions	1 Months Ended	3 Months Ended			9 Months Ended
	Oct. 31, 2014	Sep. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Sep. 30, 2017USD ($)	Sep. 30, 2018USD ($)voting_interest_model_entityvariable_interest_entitypartnership	Sep. 30, 2017USD ($)	Jan. 03, 2018USD ($)	Dec. 31, 2017USD ($)
Significant Accounting Policies and Practices
Parking services revenue		$ 362.1		$ 392.7	$ 1,091.2	$ 1,198.1
Service expense		317.1		346.8	955.6	1,054.2
Cash and cash equivalents
Restricted cash and cash equivalents		0.3			0.3			$ 0.3
Financial Instruments
Book overdrafts		26			$ 26			$ 29
Equity Investments in Unconsolidated Entities
Number of ownership interest entities | partnership					29
Gain on the sale of equity method investee				8.5		8.5
Equity earnings in related investments		$ 0.7		$ 0.6	$ 1.9	$ 10.6
Primary Beneficiary
Equity Investments in Unconsolidated Entities
Number of ownership interest entities | variable_interest_entity					24
Not Primary Beneficiary
Equity Investments in Unconsolidated Entities
Number of ownership interest entities | voting_interest_model_entity					5
Disposed of by sale | Parkmobile
Equity Investments in Unconsolidated Entities
Gross sale price							$ 19
Net gain on sale of business			$ 10.1
Parkmobile, LLC
Equity Investments in Unconsolidated Entities
Ownership percentage	30.00%

Significant Accounting Polici_5

Significant Accounting Policies and Practices - Schedule of Contract with Customer (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Assets
Notes and accounts receivable, net	$ 136.4	$ 122.3
Leasehold improvements, equipment and construction in progress, net	26.3	27.4
Other assets, net	19.1	18.3
Liabilities
Accrued expenses	30.4	25.5
Contract with customer, asset	10.8	12.2
Contract with customer, liability	16.5	$ 20.5
Accounting Standards Update 2017-10 and 2014-09
Assets
Notes and accounts receivable, net	136.4
Leasehold improvements, equipment and construction in progress, net	26.3
Other assets, net	19.1
Liabilities
Accrued expenses	30.4
Accounting Standards Update 2014-09
Liabilities
Contract with customer, asset	10.6
Contract with customer, liability	10.6
Accounting Standards Update 2017-10
Liabilities
Leasehold improvement on service concession contracts	0.5
Balances without Adoption of Topics 606 and 853 | Accounting Standards Update 2017-10 and 2014-09
Assets
Notes and accounts receivable, net	125.8
Leasehold improvements, equipment and construction in progress, net	26.8
Other assets, net	18.6
Liabilities
Accrued expenses	19.8
Impact of Adoption Increase/(Decrease) | Accounting Standards Update 2017-10 and 2014-09
Assets
Notes and accounts receivable, net	10.6
Leasehold improvements, equipment and construction in progress, net	(0.5)
Other assets, net	0.5
Liabilities
Accrued expenses	$ 10.6

Significant Accounting Polici_6

Significant Accounting Policies and Practices - Schedule of Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Parking services revenue
Revenues	$ 362.1	$ 392.7	$ 1,091.2	$ 1,198.1
Cost of parking services
Cost of parking services	317.1	346.8	955.6	1,054.2
Gross profit
Gross profit	45	45.9	135.6	143.9
Depreciation and amortization	4.2	4.9	12.7	16.3
Balances without Adoption of Topics 853 and 606 | Accounting Standards Update 2017-10 and 2014-09
Parking services revenue
Revenues	395.9		1,190.7
Cost of parking services
Cost of parking services	350.9		1,055
Gross profit
Gross profit	45		135.8
Depreciation and amortization	4.3		13
Impact of Adoption Increase/(Decrease) | Accounting Standards Update 2017-10 and 2014-09
Parking services revenue
Revenues	(33.8)		(99.5)
Cost of parking services
Cost of parking services	(33.8)		(99.4)
Gross profit
Gross profit	0		(0.2)
Depreciation and amortization	(0.1)		(0.3)
Lease type contracts
Parking services revenue
Revenues	104.7	140.9	311.6	422.6
Cost of parking services
Cost of parking services	94.2	131	283.2	387
Gross profit
Gross profit	10.5	9.9	28.4	35.6
Lease type contracts | Accounting Standards Update 2017-10
Cost of parking services
Cost of parking services	33.8		99.4
Lease type contracts | Balances without Adoption of Topics 853 and 606 | Accounting Standards Update 2017-10 and 2014-09
Parking services revenue
Revenues	138.5		411.1
Cost of parking services
Cost of parking services	128		382.6
Gross profit
Gross profit	10.5		28.5
Lease type contracts | Impact of Adoption Increase/(Decrease) | Accounting Standards Update 2017-10 and 2014-09
Parking services revenue
Revenues	(33.8)		(99.5)
Cost of parking services
Cost of parking services	(33.8)		(99.4)
Gross profit
Gross profit	0		(0.1)
Management type contracts
Parking services revenue
Revenues	82.6	86.7	264.8	262.8
Cost of parking services
Cost of parking services	48.1	50.7	157.6	154.5
Gross profit
Gross profit	34.5	36	107.2	108.3
Management type contracts | Balances without Adoption of Topics 853 and 606 | Accounting Standards Update 2017-10 and 2014-09
Parking services revenue
Revenues	82.6		264.8
Cost of parking services
Cost of parking services	48.1		157.6
Gross profit
Gross profit	34.5		107.3
Management type contracts | Impact of Adoption Increase/(Decrease) | Accounting Standards Update 2017-10 and 2014-09
Parking services revenue
Revenues	0		0
Cost of parking services
Cost of parking services	0		0
Gross profit
Gross profit	0		(0.1)
Lease and Management type contracts
Parking services revenue
Revenues	187.3	227.6	576.4	685.4
Cost of parking services
Cost of parking services	142.3	181.7	440.8	541.5
Lease and Management type contracts | Balances without Adoption of Topics 853 and 606 | Accounting Standards Update 2017-10 and 2014-09
Parking services revenue
Revenues	221.1		675.9
Cost of parking services
Cost of parking services	176.1		540.2
Lease and Management type contracts | Impact of Adoption Increase/(Decrease) | Accounting Standards Update 2017-10 and 2014-09
Parking services revenue
Revenues	(33.8)		(99.5)
Cost of parking services
Cost of parking services	(33.8)		(99.4)
Reimbursed management type contract
Parking services revenue
Revenues	174.8	165.1	514.8	512.7
Cost of parking services
Cost of parking services	174.8	$ 165.1	514.8	$ 512.7
Reimbursed management type contract | Balances without Adoption of Topics 853 and 606 | Accounting Standards Update 2017-10 and 2014-09
Parking services revenue
Revenues	174.8		514.8
Cost of parking services
Cost of parking services	174.8		514.8
Reimbursed management type contract | Impact of Adoption Increase/(Decrease) | Accounting Standards Update 2017-10 and 2014-09
Parking services revenue
Revenues	0		0
Cost of parking services
Cost of parking services	$ 0		$ 0

Revenue - Narrative (Details)

Revenue - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Revenue from Contract with Customer [Abstract]
Performance obligation unsatisfied or partially satisfied	$ 106,700,000		$ 106,700,000
Contract cost, accumulated amortization	8,200,000		8,200,000		$ 8,900,000
Capitalized cost, impairment	$ 0	$ 0	$ 0	$ 0

Revenue - Schedule of Performan

Revenue - Schedule of Performance Obligation (Details) $ in Millions	Sep. 30, 2018USD ($)
Revenue from Contract with Customer [Abstract]
Remaining Performance Obligations	$ 106.7
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-10-01
Revenue from Contract with Customer [Abstract]
Remaining Performance Obligations	$ 13.1
Revenue, remaining performance obligation, expected timing of satisfaction, period	3 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-01-01
Revenue from Contract with Customer [Abstract]
Remaining Performance Obligations	$ 38.3
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue from Contract with Customer [Abstract]
Remaining Performance Obligations	$ 24.9
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue from Contract with Customer [Abstract]
Remaining Performance Obligations	$ 12.8
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue from Contract with Customer [Abstract]
Remaining Performance Obligations	$ 8
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue from Contract with Customer [Abstract]
Remaining Performance Obligations	$ 9.6
Revenue, remaining performance obligation, expected timing of satisfaction, period

Revenue - Schedule of Contract

Revenue - Schedule of Contract Asset and Liability (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Revenue from Contract with Customer [Abstract]
Accounts receivable	$ 125.6
Contract asset	10.8	$ 12.2
Contract liability	$ (16.5)	$ (20.5)

Revenue - Schedule of Contrac_2

Revenue - Schedule of Contract Asset Balances (Details) $ in Millions	9 Months Ended
	Sep. 30, 2018USD ($)
Contract Asset Balances with Customer [Roll Forward]
Balance as of January 1, 2018	$ 12.2
Additional contract assets	100
Reclassification to accounts receivable	(101.4)
Balance as of September 30, 2018	$ 10.8

Revenue - Schedule of Contrac_3

Revenue - Schedule of Contract Liability Balances (Details) $ in Millions	9 Months Ended
	Sep. 30, 2018USD ($)
Contract Liability Balances with Customer [Roll Forward]
Balance as of January 1, 2018	$ (20.5)
Additional contract liabilities	(128.6)
Recognition of revenue from contract liabilities	132.6
Balance as of September 30, 2018	$ (16.5)

Revenue - Schedule of Amortizat

Revenue - Schedule of Amortization Expense Related to Cost of Contracts (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Revenue from Contract with Customer [Abstract]
Amortization expense related to contract cost	$ 0.8	$ 0.8	$ 2.3	$ 2.5

Restructuring, Merger and Acq_3

Restructuring, Merger and Acquisition Related Costs - Narrative (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Acquisitions
Accrual for restructuring, merger and integration costs	$ 2	$ 2.3
Compensation and Payroll Withholdings
Acquisitions
Accrual for restructuring, merger and integration costs	1.1	1.8
Accrued Liabilities
Acquisitions
Accrual for restructuring, merger and integration costs	0.5
Other long-term Liabilities
Acquisitions
Accrual for restructuring, merger and integration costs	$ 0.4	$ 0.5

Restructuring, Merger and Acq_4

Restructuring, Merger and Acquisition Related Costs - Schedule of Acquisition Related Costs (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
General and administrative expenses | Central Merger
Acquisitions
Acquisition and integration related costs included in general and administrative expenses	$ 0.6	$ 0	$ 3.4	$ 1.1

Other Intangible Assets, net (D

Other Intangible Assets, net (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Intangible assets, net
Weighted Average Life			10 years 2 months 12 days
Acquired Intangible Assets, Gross	$ 126.3		$ 126.3		$ 126.3
Accumulated Amortization	(76.2)		(76.2)		(72.2)
Acquired Intangible Assets, Net	50.1		50.1		54.1
Amortization expense related to other intangible assets included in depreciation and amortization	1.3	$ 1.4	$ 4	$ 5.9
Minimum
Intangible assets, net
Weighted Average Life			6 months
Maximum
Intangible assets, net
Weighted Average Life			14 years
Covenant not to compete
Intangible assets, net
Weighted Average Life			3 months 18 days
Acquired Intangible Assets, Gross	0.9		$ 0.9		0.9
Accumulated Amortization	(0.9)		(0.9)		(0.9)
Acquired Intangible Assets, Net	0		$ 0		0
Trade names and trademarks
Intangible assets, net
Weighted Average Life			9 months 18 days
Acquired Intangible Assets, Gross	9.8		$ 9.8		9.8
Accumulated Amortization	(9.7)		(9.7)		(9.7)
Acquired Intangible Assets, Net	0.1		$ 0.1		0.1
Proprietary know how
Intangible assets, net
Weighted Average Life			9 months 18 days
Acquired Intangible Assets, Gross	34.6		$ 34.6		34.6
Accumulated Amortization	(34.6)		(34.6)		(34.5)
Acquired Intangible Assets, Net	0		$ 0		0.1
Management contract rights
Intangible assets, net
Weighted Average Life			10 years 2 months 12 days
Acquired Intangible Assets, Gross	81		$ 81		81
Accumulated Amortization	(31)		(31)		(27.1)
Acquired Intangible Assets, Net	$ 50		$ 50		$ 53.9

Goodwill (Details)

Goodwill (Details) $ in Millions	9 Months Ended
	Sep. 30, 2018USD ($)
Changes in carrying amounts of goodwill
December 31, 2017	$ 431.7
Foreign currency translation	(0.1)
September 30, 2018	431.6
Region One
Changes in carrying amounts of goodwill
December 31, 2017	369
Foreign currency translation	(0.1)
September 30, 2018	368.9
Region Two
Changes in carrying amounts of goodwill
December 31, 2017	62.7
Foreign currency translation	0
September 30, 2018	$ 62.7

Fair Value Measurement - Additi

Fair Value Measurement - Additional Information (Details) - USD ($)	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Nonrecurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment charges	$ 0	$ 0

Fair Value Measurement - Carryi

Fair Value Measurement - Carrying Value and Estimated Fair Value (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Fair Value Measurement
Long-term borrowings	$ 107.8	$ 153.8
Restated Credit Facility, net of original discount on borrowings and deferred financing costs
Fair Value Measurement
Long-term borrowings	105.2	151
Restated Credit Facility, net of original discount on borrowings and deferred financing costs | Carrying Amount
Fair Value Measurement
Long-term borrowings	105.2	151
Restated Credit Facility, net of original discount on borrowings and deferred financing costs | Fair Value
Fair Value Measurement
Long-term borrowings	105.2	151
Other borrowings
Fair Value Measurement
Long-term borrowings	2.6	2.8
Other borrowings | Carrying Amount
Fair Value Measurement
Long-term borrowings	2.6	2.8
Other borrowings | Fair Value
Fair Value Measurement
Long-term borrowings	$ 2.6	$ 2.8

Borrowing Arrangements - Schedu

Borrowing Arrangements - Schedule of Long-Term Borrowing (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Total obligations under Restated Credit Facility and other borrowings	$ 107.8	$ 153.8
Less: Current portion of obligations under Restated Credit Facility and other borrowings	20.9	20.6
Total long-term obligations under Restated Credit Facility and other borrowings	86.9	133.2
Restated Credit Facility, net of original discount on borrowings and deferred financing costs
Debt Instrument [Line Items]
Total obligations under Restated Credit Facility and other borrowings	105.2	151
Other borrowings
Debt Instrument [Line Items]
Total obligations under Restated Credit Facility and other borrowings	$ 2.6	$ 2.8

Borrowing Arrangements - Amende

Borrowing Arrangements - Amended and Restated Credit Facility (Details)	Feb. 20, 2015USD ($)	Sep. 30, 2018USD ($)	Jun. 30, 2018USD ($)	Sep. 30, 2015	Sep. 30, 2018USD ($)	Sep. 30, 2017USD ($)	Sep. 30, 2016	Feb. 20, 2020	Dec. 31, 2017USD ($)
Debt Instrument [Line Items]
Debt repayment					$ 101,600,000	$ 308,700,000
Long-term borrowings		$ 107,800,000			107,800,000				$ 153,800,000
Restated Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 400,000,000
Debt repayment		20,000,000	$ 15,000,000
Senior credit facility, net of discount
Debt Instrument [Line Items]
Long-term borrowings		105,200,000			105,200,000				$ 151,000,000
Senior credit facility, net of discount | Restated Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity	200,000,000
Current borrowing capacity		145,900,000			145,900,000
Letters of credit outstanding		48,100,000			48,100,000
Discount on debt		400,000			400,000
Deferred financing cost					500,000
Letter of credit facility | Restated Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity	100,000,000
Swingline Loans | Restated Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity	20,000,000
Term loan facility | Restated Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity	200,000,000
Year one amortization of principal	15,000,000
Year two amortization of principal	15,000,000
Year three amortization of principal	20,000,000
Year four amortization of principal	20,000,000
Year five amortization of principal	20,000,000
Year six amortization of principal	110,000,000
Revolving credit facility | Restated Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 100,000,000
LIBOR Loans | Senior credit facility, net of discount | Restated Credit Agreement
Debt Instrument [Line Items]
Period of total debt to EBITDA ratio	12 months
Base rate loans | Senior credit facility, net of discount | Restated Credit Agreement | Federal funds
Debt Instrument [Line Items]
Interest rate margin on variable rate basis	0.50%
Base rate loans | Senior credit facility, net of discount | Restated Credit Agreement | LIBOR
Debt Instrument [Line Items]
Interest rate margin on variable rate basis	1.00%
Credit Agreement | Senior credit facility, net of discount | Restated Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 145,920,000			$ 145,920,000
Maximum | Senior credit facility, net of discount | Restated Credit Agreement
Debt Instrument [Line Items]
Total debt to EBITDA ratio that is required to be maintained				4			3.75
Minimum | Senior credit facility, net of discount | Restated Credit Agreement
Debt Instrument [Line Items]
Fixed charge coverage ratio that is required to be maintained	1.25
Forecast | Maximum | Senior credit facility, net of discount | Restated Credit Agreement
Debt Instrument [Line Items]
Total debt to EBITDA ratio that is required to be maintained								3.5

Share Repurchase Plan (Details)

Share Repurchase Plan (Details) - USD ($)	9 Months Ended		29 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	May 31, 2016
Equity [Abstract]
Amount authorized by the company's Board of Directors (not more than)				$ 30,000,000
Common stock repurchased under share repurchase program (in shares)	0	0	305,183
Average cost per share (in dollars per share)			$ 24.43
Amount of program-to-date purchases			$ 7,500,000

Bradley Agreement - Additional

Bradley Agreement - Additional Information (Details) - Bradley International Airport parking facilities operating agreement	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018USD ($)	Sep. 30, 2017USD ($)	Sep. 30, 2018USD ($)parking_space	Sep. 30, 2017USD ($)	Dec. 31, 2024USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2002USD ($)	Dec. 31, 2025USD ($)
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Agreement period for operation of parking spaces			25 years
Number of garage parking spaces at Bradley International Airport operated | parking_space			3,500
Annual minimum guaranteed payment to the State by the trustee							$ 11,500,000
Maximum premium percentage on initial deficiency payment (not more than)			10.00%
Estimated accrued deficiency payments	$ 0		$ 0				0
Management fee apportioned to the entity (as a percent)			60.00%
Management fee apportioned to an un-affiliated entity (as a percent)			40.00%
Unrecognized cumulative management fees	18,500,000		$ 18,500,000				$ 17,700,000
Management fees	$ 0	$ 0	$ 0	$ 0
Minimum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Annual minimum guaranteed payment to the State by the trustee								$ 8,300,000
State of Connecticut special facility revenue bonds | Minimum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Annual principal and interest on revenue bonds								$ 3,600,000
Forecast
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Annual minimum guaranteed payment to the State by the trustee						$ 11,800,000
Forecast | Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Annual minimum guaranteed payment to the State by the trustee					$ 13,200,000
Forecast | State of Connecticut special facility revenue bonds | Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Annual principal and interest on revenue bonds									$ 4,500,000

Bradley Agreement - Deficiency

Bradley Agreement - Deficiency Payments, Net of Reimbursements (Details) $ in Millions	9 Months Ended
	Sep. 30, 2018USD ($)
Gain Contingency [Roll Forward]
Balance at the beginning of the year	$ 7.8
Deficiency payments made	0.1
Deficiency repayments received	(3)
Balance at the beginning of the year	$ 4.9

Bradley Agreement - Schedule of

Bradley Agreement - Schedule of Interest and Premium Received and Deficiency Payments (Details) - Bradley International Airport parking facilities operating agreement - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Loss Contingencies [Line Items]
Deficiency repayments	$ 0.9	$ 0.5	$ 2.9	$ 1.7
Interest	0	0	0.5	0.2
Premium	$ 0.1	$ 0	$ 0.2	$ 0.2

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock Options and Grants (Details) - Stock Options - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options or grants (in shares)	12,736	16,428
Recognized stock-based compensation expense	$ 0.5	$ 0.5

Stock-Based Compensation - Rest

Stock-Based Compensation - Restricted Stock Units (Details) - Restricted Stock Units - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized (in shares)	52,306	0
Vested (in shares)	129,706	4,399
Unrecognized stock-based compensation costs	$ 2
Weighted average remaining recognition period of unrecognized stock-based compensation costs	2 years 4 months 24 days
Long-term incentive plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forfeited (in shares)	6,456	4,537

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of Compensation Expense Related to Restricted Stock Unit (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 0.3	$ 0.2	$ 0.6	$ 0.6

Stock-Based Compensation - Perf

Stock-Based Compensation - Performance Share Units (Details) - Performance share units - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average remaining recognition period of unrecognized stock-based compensation costs	1 year 9 months 18 days
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs related to unvested options (up to)	$ 12.9
Long-term incentive plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forfeited (in shares)	10,572	11,770
Executive Management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Executive Management | Long-term incentive plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock unit granted to an executive (in shares)	28,060	76,120
Adjustments based in shares expected to vest (in shares)	70,661
Vested (in shares)	6,874	14,195

Stock-Based Compensation - Sc_2

Stock-Based Compensation - Schedule of Compensation Expense Related to Performance Share Units (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Performance share units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ (0.4)	$ 0.6	$ 0.7	$ 1.8

Net Income per Common Share - W

Net Income per Common Share - Weighted Average Common Shares Outstanding (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share [Abstract]
Net income attributable to SP Plus Corporation	$ 13.5	$ 11.2	$ 44.1	$ 33.4
Basic weighted average common shares outstanding (in shares)	22,439,884	22,203,023	22,370,789	22,186,556
Dilutive impact of share-based awards (in shares)	186,862	320,013	236,485	314,822
Diluted weighted average common shares outstanding (in shares)	22,626,746	22,523,036	22,607,274	22,501,378
Net income per common share
Basic (in dollars per share)	$ 0.60	$ 0.51	$ 1.97	$ 1.51
Diluted (in dollars per share)	$ 0.60	$ 0.50	$ 1.95	$ 1.48

Net Income per Common Share - A

Net Income per Common Share - Additional Information (Details)	9 Months Ended
	Sep. 30, 2018shares
Earnings Per Share [Abstract]
Potential shares of common stock attributable to stock options excluded from net income per common share calculation (in shares)	0

Comprehensive Income - Componen

Comprehensive Income - Components of Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Net income	$ 14.5	$ 12	$ 46.6	$ 36
Effective portion of unrealized loss on cash flow hedge	0	(0.1)	0	0
Foreign currency translation	0.1	0.2	(0.4)	0.2
Comprehensive income	14.6	12.1	46.2	36.2
Less: Comprehensive income attributable to noncontrolling interest	1	0.8	2.5	2.6
Comprehensive income attributable to SP Plus Corporation	$ 13.6	$ 11.3	$ 43.7	$ 33.6

Comprehensive Income - Compon_2

Comprehensive Income - Components of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance as of December 31, 2017			$ 313.1
Change in other comprehensive loss	$ 0.1	$ 0.1	(0.4)	$ 0.2
Balance as of September 30, 2018	358.7		358.7
Foreign Currency Translation Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance as of December 31, 2017			(1.2)
Change in other comprehensive loss			(0.4)
Balance as of September 30, 2018	(1.6)		(1.6)
Total Accumulated Other Comprehensive Loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance as of December 31, 2017			(1.2)
Balance as of September 30, 2018	$ (1.6)		$ (1.6)

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Tax Disclosure [Abstract]
Income tax expense	$ 5.6	$ 7.3	$ 16.9	$ 21.3
Pre-tax earnings (loss)	20.1	$ 19.3	$ 63.5	$ 57.3
Effective tax rate (as a percent)			26.60%	37.20%
Income tax benefit related to Tax Cuts and Jobs Act	1.2
Uncertain tax position	0.3		$ 0.3
Interest expense due to state examination	$ 0.2

Business Unit Segment Informa_3

Business Unit Segment Information - Additional Information (Details)	9 Months Ended
	Sep. 30, 2018segment
Segment Reporting [Abstract]
Number of operating segments	2

Business Unit Segment Informa_4

Business Unit Segment Information - Schedule of Revenues and Gross Profit by Regions (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Parking Services Revenue
Revenues	$ 362.1	$ 392.7	$ 1,091.2	$ 1,198.1
Gross Profit
Total gross profit	45	45.9	135.6	143.9
General and administrative expenses	$ 18.7	$ 19.6	$ 63.3	$ 63.3
General and administrative expense percentage of gross profit	42.00%	43.00%	47.00%	44.00%
Depreciation and amortization	$ 4.2	$ 4.9	$ 12.7	$ 16.3
Operating income	22.1	21.4	59.6	64.3
Other expenses (income)
Interest expense	2.1	2.2	6.5	7.1
Interest expense	(0.1)	(0.2)	(0.3)	(0.5)
Gain on sale of a business	0	0	0	(0.1)
Equity losses (earnings) from investment in unconsolidated entity	0	0.1	(10.1)	0.5
Total other expenses (income)	2	2.1	(3.9)	7
Earnings before income taxes	20.1	19.3	63.5	57.3
Income tax expense	5.6	7.3	16.9	21.3
Net income	14.5	12	46.6	36
Less: Net income attributable to noncontrolling interest	1	0.8	2.5	2.6
Net income attributable to SP Plus Corporation	13.5	11.2	44.1	33.4
Operating segment | Region One
Parking Services Revenue
Revenues	157	171.4	481.9	516.1
Gross Profit
Total gross profit	31.8	33.1	91.3	103.6
Operating segment | Region Two
Parking Services Revenue
Revenues	28	54.2	86.5	163
Gross Profit
Total gross profit	8.7	7.8	25.9	24.4
Segment Reconciling Items
Parking Services Revenue
Revenues	2.3	2	8	6.3
Gross Profit
Total gross profit	4.5	5	18.4	15.9
Lease type contracts
Parking Services Revenue
Revenues	104.7	140.9	311.6	422.6
Gross Profit
Total gross profit	10.5	9.9	28.4	35.6
Lease type contracts | Operating segment
Gross Profit
Total gross profit
Lease type contracts | Operating segment | Region One
Parking Services Revenue
Revenues	97.6	108.9	290.8	326
Gross Profit
Total gross profit	$ 7.7	$ 7.8	$ 19.5	$ 28.9
Gross margin percentage	8.00%	7.00%	7.00%	9.00%
Lease type contracts | Operating segment | Region Two
Parking Services Revenue
Revenues	$ 6.9	$ 32	$ 20.3	$ 96.6
Gross Profit
Total gross profit	$ 2	$ 1.6	$ 5.6	$ 4.9
Gross margin percentage	29.00%	5.00%	28.00%	5.00%
Lease type contracts | Segment Reconciling Items
Parking Services Revenue
Revenues	$ 0.2	$ 0	$ 0.5	$ 0
Gross Profit
Total gross profit	$ 0.8	$ 0.5	$ 3.3	$ 1.8
Gross margin percentage	400.00%	0.00%	660.00%	0.00%
Management type contracts
Parking Services Revenue
Revenues	$ 82.6	$ 86.7	$ 264.8	$ 262.8
Gross Profit
Total gross profit	34.5	36	107.2	108.3
Management type contracts | Operating segment
Gross Profit
Total gross profit
Management type contracts | Operating segment | Region One
Parking Services Revenue
Revenues	59.4	62.5	191.1	190.1
Gross Profit
Total gross profit	$ 24.1	$ 25.3	$ 71.8	$ 74.7
Gross margin percentage	41.00%	40.00%	38.00%	39.00%
Management type contracts | Operating segment | Region Two
Parking Services Revenue
Revenues	$ 21.1	$ 22.2	$ 66.2	$ 66.4
Gross Profit
Total gross profit	$ 6.7	$ 6.2	$ 20.3	$ 19.5
Gross margin percentage	32.00%	28.00%	31.00%	29.00%
Management type contracts | Segment Reconciling Items
Parking Services Revenue
Revenues	$ 2.1	$ 2	$ 7.5	$ 6.3
Gross Profit
Total gross profit	$ 3.7	$ 4.5	$ 15.1	$ 14.1
Gross margin percentage	176.00%	225.00%	201.00%	224.00%
Reimbursed management type contract
Parking Services Revenue
Revenues	$ 174.8	$ 165.1	$ 514.8	$ 512.7

Subsequent Event (Details)

Subsequent Event (Details) $ in Millions	Oct. 16, 2018USD ($)
Bags | Subsequent Event
Subsequent Event [Line Items]
Cash purchase price	$ 275