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Significant Accounting Policies and Practices - Narrative (Details)	1 Months Ended		3 Months Ended	12 Months Ended
	Aug. 31, 2015 USD ($)	Oct. 31, 2014	Mar. 31, 2018 USD ($)	Dec. 31, 2019 USD ($) voting_interest_model_entity variable_interest_entity partnership	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2015 USD ($)	Jan. 03, 2018 USD ($)
Significant Accounting Policies [Line Items]
Cash and cash equivalents restricted to withdrawals				$ 500,000	$ 1,700,000
Allowance for doubtful accounts				1,900,000	1,000,000.0
Impairment loss as a result of goodwill				$ 0	0	$ 0
Forecasted period for income statement and working capital projections to assess goodwill impairment				5 years
Book overdrafts				$ 29,300,000	34,000,000.0
Gain on sale of equity method Investee						8,500,000
Equity earnings in related investments				3,200,000	2,700,000	11,300,000
Cash received from sale of a business, net of cash disposed				0	0	600,000
Right-of-use assets				$ 431,700,000	0
Discontinued Operations, Disposed of by Sale \| Parkmobile
Significant Accounting Policies [Line Items]
Sale price of business								$ 19,000,000.0
Gain on sale of business			$ 10,100,000
Discontinued Operations, Disposed of by Sale \| Security Business
Significant Accounting Policies [Line Items]
Sale price of business	$ 1,800,000
Gain on sale of business	$ 500,000
Cash received from sale of a business, net of cash disposed							$ 1,000,000.0
Period of cash consideration to be received							18 months
Contingent consideration receivable from sale of business						600,000	$ 500,000
Additional earn out consideration						$ 100,000
Minimum
Significant Accounting Policies [Line Items]
Voting interest ownership percentage (in percentage)				30.00%
Maximum
Significant Accounting Policies [Line Items]
Voting interest ownership percentage (in percentage)				50.00%
Equipment \| Minimum
Significant Accounting Policies [Line Items]
Ranges of estimated useful life				1 year
Equipment \| Maximum
Significant Accounting Policies [Line Items]
Ranges of estimated useful life				10 years
Leasehold improvements \| Maximum
Significant Accounting Policies [Line Items]
Ranges of estimated useful life				10 years
Leasehold improvements \| Average
Significant Accounting Policies [Line Items]
Ranges of estimated useful life				4 years 7 months 6 days
Partnerships and joint ventures
Significant Accounting Policies [Line Items]
Number of ownership interest entities (number of partnerships) \| partnership				30
Variable Interest Entity, Primary Beneficiary
Significant Accounting Policies [Line Items]
Number of ownership interest entities (number of partnerships) \| variable_interest_entity				25
Variable Interest Entity, Not Primary Beneficiary
Significant Accounting Policies [Line Items]
Number of ownership interest entities (number of partnerships) \| voting_interest_model_entity				5
Accounting Standards Update 2018-02
Significant Accounting Policies [Line Items]
Tax Cuts and Jobs Act, reclassification from AOCI to retained earnings, tax effect					$ 600,000
Parkmobile, LLC
Significant Accounting Policies [Line Items]
Ownership percentage (in percentage)		30.00%