Goodwill

The amounts for goodwill and changes to carrying value by reportable segment are as follows:



(millions)	Region One		Region Two		Total
Balance as of December 31, 2015	$	368.6	$	62.7	$	431.3
Foreign currency translation	0.1		—		0.1
Balance as of December 31, 2016	$	368.7	$	62.7	$	431.4
Foreign currency translation	0.3		—		0.3
Balance as of December 31, 2017	$	369.0	$	62.7	$	431.7

The Company tests goodwill at least annually for impairment (the Company has elected to annually test for potential impairment of goodwill on the first day of the fourth quarter) and tests more frequently if indicators are present or changes in circumstances suggest that impairment may exist. The indicators include, among others, declines in sales, earning or cash flows or the development of a material adverse change in business climate. The Company assesses goodwill for impairment at the reporting unit level, which is defined as an operating segment or one level below an operating segment, referred to as a reporting unit. See Note 1. Significant Accounting Policies and Practices for additional detail on the Company's policy for assessing goodwill for impairment.

Due to a change in the Company’s segment reporting effective January 1, 2017, the goodwill allocated to certain previous reporting units have been aggregated into a single operating segment. The reporting units are reported as Region One (Commercial) and Region Two (Airport Transportation). See also Note 19. Domestic and Foreign Operations for further disclosure on the Company’s change in reporting segments effective January 1, 2017.

As a result of the change in internal reporting segment information, the Company completed a quantitative test (Step One) of goodwill impairment as of January 1, 2017 and concluded that the estimated fair values of each of the Company’s reporting units exceeded its carrying amount of net assets assigned to that reporting unit and therefore no further testing was required (Step Two). In conducting the January 1, 2017 goodwill impairment quantitative test (Step One), the Company analyzed actual and projected growth trends of the reporting units, gross margin, operating expenses and Earnings Before Interest, Taxes, Depreciation and Amortization (“EBITDA”) (which also includes forecasted five-year income statement and working capital projection, a market-based weighted average cost of capital and terminal values after five years). The Company also assesses critical areas that may impact its business including economic conditions, market related exposures, competition, changes in service offerings and changes in key personnel. As part of the January 1, 2017 goodwill assessment, the Company engaged a third-party to evaluate its reporting units’ fair values. No impairment was recorded as a result of the goodwill impairment test performed.

The Company completed its annual goodwill impairment test as of October 1, 2017, using a qualitative test (Step Zero), to determine the likelihood of impairment and if it was more likely than not that the fair value of the reporting units were less than the carrying value of the reporting unit. The Company concluded that the estimated fair values of each of the Company's reporting units exceeded its carrying amount of net assets assigned to that reporting unit and, therefore, no further testing was required (Step One). Generally, the more-likely-than-not threshold is a greater than a 50% likelihood that the fair value of a reporting unit is greater than the carrying value. As part of the October 1, 2017 goodwill assessment, the Company engaged a third-party to estimate a discount rate, which is a primary driver in the valuation of the Company's reporting units' fair values.