Goodwill and Other Intangible Assets (Tables)

3 Months Ended

Mar. 31, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Changes in Carrying Amount of Goodwill

Changes in the carrying amount of goodwill were as follows:

(in millions)	Truckload		Logistics		Other		Total
Balance at December 31, 2017	$	138.2	$	14.2	$	12.4	$	164.8
Foreign currency translation	—		—		0.5		0.5
Balance at March 31, 2018	$	138.2	$	14.2	$	12.9	$	165.3

Schedule of Identifiable Intangible Assets Other Than Goodwill

The identifiable intangible assets other than goodwill listed below are included in other noncurrent assets on the consolidated balance sheets.

	March 31, 2018						December 31, 2017
(in millions)	Gross Carrying Amount		Accumulated Amortization		Net Carrying Amount		Gross Carrying Amount		Accumulated Amortization		Net Carrying Amount
Customer lists	$	10.5	$	2.7	$	7.8	$	10.5	$	2.5	$	8.0
Trade names	1.4		0.9		0.5		1.4		0.7		0.7
Total intangible assets	$	11.9	$	3.6	$	8.3	$	11.9	$	3.2	$	8.7

Schedule Estimated Future Amortization Expense

Estimated future amortization expense related to intangible assets is as follows (in millions):

Remaining 2018	$	1.0
2019	1.1
2020	1.0
2021	1.0
2022	1.0
2023 and thereafter	3.2
	$	8.3