Other Intangible Assets

12 Months Ended

Dec. 31, 2019

Goodwill and Intangible Assets Disclosure [Abstract]

A summary of our identifiable intangible assets are as follows (in millions):



As of December 31, 2019	Useful Life	Gross		Accumulated Amortization			Net
Intangible Assets subject to amortization:
Third-party fuel supply agreement	10 years	$	49.0	$	(12.3	)	$	36.7
Fuel trade name	5 years	4.0		(2.0		)	2.0
Intangible assets not subject to amortization:
Rights-of-way	Indefinite	48.9					48.9
Line space history	Indefinite	12.0					12.0
Liquor licenses	Indefinite	8.5					8.5
Refinery permits	Indefinite	2.2					2.2
Total		$	124.6	$	(14.3	)	$	110.3



As of December 31, 2018	Useful Life	Gross		Accumulated Amortization			Net
Intangible Assets subject to amortization:
Third-party fuel supply agreement	10 years	49.0		(7.4		)	41.6
Fuel trade name	5 years	4.0		(1.2		)	2.8
Below market leases	13 - 15 years	8.3		(0.3		)	8.0
Intangible assets not subject to amortization:
Rights-of-way	Indefinite	30.0					30.0
Line space history	Indefinite	11.3					11.3
Liquor licenses	Indefinite	8.5					8.5
Refinery permits	Indefinite	2.2					2.2
Total		$	113.3	$	(8.9	)	$	104.4

Amortization of intangible assets was $5.7 million, $6.1 million, and $3.8 million during the years ended December 31, 2019, 2018 and 2017, respectively, and is included in depreciation and amortization on the accompanying consolidated statements of income, with the exception of an immaterial amount related to below market leases.

Amortization expense for the next five years is estimated to be as follows (in millions):



2020	$	5.7
2021	$	5.7
2022	$	5.3
2023	$	4.9
2024	$	4.9