Long-Lived Assets (Policies)	6 Months Ended
	Jun. 30, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible Assets	Our identifiable intangible assets primarily consist of acquired permits and leasehold agreements, and franchise agreements, which grant us the right to operate out-of-home structures in specified locations and the right to provide advertising space on railroad and municipal transit properties. Identifiable intangible assets are amortized on a straight-line basis over their estimated useful life, which is the respective life of the agreement that in some cases includes historical experience of renewals.
Direct Lease Acquisition Costs	Direct lease acquisition costs are amortized on a straight-line basis over the related customer lease term, which generally ranges from four weeks to one year.