Annual report pursuant to Section 13 and 15(d)

Intangible Assets and Amortization Method (Detail)

v3.8.0.1
Intangible Assets and Amortization Method (Detail)
12 Months Ended
Dec. 31, 2017
Finite Lived Intangible Assets [Line Items]  
Goodwill Indefinite-lived
Tradename Indefinite-lived
Vendor Contracts  
Finite Lived Intangible Assets [Line Items]  
Finite-Lived Intangible Assets, Amortization Method Straight-line method over the terms of the underlying contracts. The remaining terms of the underlying contracts range from one to three years.
Vendor Contracts | Minimum  
Finite Lived Intangible Assets [Line Items]  
Finite-Lived Intangible Asset, Useful Life 1 year
Vendor Contracts | Maximum  
Finite Lived Intangible Assets [Line Items]  
Finite-Lived Intangible Asset, Useful Life 3 years
Favorable/unfavorable leases  
Finite Lived Intangible Assets [Line Items]  
Finite-Lived Intangible Assets, Amortization Method Based on the pattern in which the economic benefits are realized over the terms of the lease agreements. The remaining terms of the lease agreements range from approximately two to nineteen years.
Favorable/unfavorable leases | Minimum  
Finite Lived Intangible Assets [Line Items]  
Finite-Lived Intangible Asset, Useful Life 2 years
Favorable/unfavorable leases | Maximum  
Finite Lived Intangible Assets [Line Items]  
Finite-Lived Intangible Asset, Useful Life 19 years
Other Intangible Assets  
Finite Lived Intangible Assets [Line Items]  
Finite-Lived Intangible Assets, Amortization Method Straight-line method over the terms of the underlying agreement or the expected useful life of the intangible asset. The remaining useful lives of these intangible assets range from one to twelve years.
Other Intangible Assets | Minimum  
Finite Lived Intangible Assets [Line Items]  
Finite-Lived Intangible Asset, Useful Life 1 year
Other Intangible Assets | Maximum  
Finite Lived Intangible Assets [Line Items]  
Finite-Lived Intangible Asset, Useful Life 12 years