15.

Business Segments and Major Customers

We operate our business through three operating segments: Commercial Aviation North America, or “CA-NA”, Commercial Aviation Rest of World, or “CA-ROW,” and Business Aviation, or “BA”. See Note 1, “Basis of Presentation,” for further information regarding our segments.

The accounting policies of the operating segments are the same as those described in Note 2, “Summary of Significant Accounting Policies,” in our 2017 10-K. Intercompany transactions between segments are excluded as they are not included in management’s performance review of the segments. For the three months ended March 31, 2018 and 2017, our foreign revenue accounts for less than 10% of our consolidated revenue. We do not segregate assets between segments for internal reporting. Therefore, asset-related information has not been presented. We do not disclose assets outside of the United States as they totaled less than 10% of our unaudited condensed consolidated assets as of March 31, 2018 and December 31, 2017. For our airborne assets, we consider only those assets installed in aircraft associated with international commercial airline partners to be owned outside of the United States.

Management evaluates performance and allocates resources to each segment based on segment profit (loss), which is calculated internally as net income (loss) attributable to common stock before interest expense, interest income, income taxes, depreciation and amortization, certain non-cash items (including amortization of deferred airborne lease incentives, stock-based compensation expense, amortization of STC costs and the accounting impact of the transition to airline-directed model) and other income (expense). Segment profit (loss) is a measure of performance reported to the chief operating decision maker for purposes of making decisions about allocating resources to the segments and evaluating segment performance. In addition, segment profit (loss) is included herein in conformity with ASC 280-10, Segment Reporting. Management believes that segment profit (loss) provides useful information for analyzing and evaluating the underlying operating results of each segment. However, segment profit (loss) should not be considered in isolation or as a substitute for net income (loss) attributable to common stock or other measures of financial performance prepared in accordance with GAAP. Additionally, our computation of segment profit (loss) may not be comparable to other similarly titled measures computed by other companies.

Information regarding our reportable segments is as follows (in thousands):


	For the Three Months Ended
	March 31, 2018
	CA-NA		CA-ROW			BA		Total
Service revenue	$	88,783	$	14,245		$	47,650	$	150,678
Equipment revenue (1)		55,038		4,924			21,185		81,147

Total revenue	$	143,821	$	19,169		$	68,835	$	231,825

Segment profit (loss)	$	1,656	$	(22,605	)	$	32,323	$	11,374


	For the Three Months Ended
	March 31, 2017
	CA-NA		CA-ROW			BA		Total
Service revenue	$	97,145	$	9,368		$	39,982	$	146,495
Equipment revenue		1,671		918			16,322		18,911

Total revenue	$	98,816	$	10,286		$	56,304	$	165,406

Segment profit (loss)	$	11,159	$	(26,555	)	$	26,115	$	10,719

(1)	CA-NA equipment revenue for the three months ended March 31, 2018 includes the accounting impact of the transition of one of our airline partners to the airline-directed model. See Note 1, “Basis of Presentation” for additional information.

A reconciliation of segment profit (loss) to the relevant consolidated amounts is as follows (in thousands):


	For the Three Months
	Ended March 31,
	2018			2017
CA-NA segment profit	$	1,656		$	11,159
CA-ROW segment loss		(22,605	)		(26,555	)
BA segment profit		32,323			26,115

Total segment profit		11,374			10,719
Interest income		1,076			545
Interest expense		(30,554	)		(26,943	)
Depreciation and amortization		(35,919	)		(30,435	)
Transition to airline-directed model		19,302			—
Amortization of deferred airborne lease incentives ⁽¹⁾		7,630			9,348
Amortization of STC costs		(172	)		—
Stock-based compensation expense		(4,386	)		(4,330	)
Other income (expense)		505			(38	)

Loss before income taxes	$	(31,144	)	$	(41,134	)

(1)

Amortization of deferred airborne lease incentive relates to our CA-NA and CA-ROW segments. See Note 11, “Leases,” for further information.

Major Customers and Airline Partnerships — Under the turnkey model, we refer to the airline as a “partner”, and under the airline-directed model, we refer to the airline as a “customer.”

During the three month period ended March 31, 2018, American Airlines accounted for approximately 36% of consolidated revenue while no other customer accounted for more than 10% of consolidated revenue during the prior year period. Revenue earned from American Airlines for the three month period ended March 31, 2018 included $45.4 million of equipment revenue recognized due to its transition to the airline-directed model. See Note 1, “Basis of Presentation,” for additional information. Revenue earned from passengers on aircraft operated by American Airlines, which was under the turnkey model during the three month period ended March 31, 2017, accounted for approximately 23% of consolidated revenue during such period.

Revenue earned from passengers on aircraft operated by Delta Air Lines, which is under the turnkey model, accounted for approximately 20% and 25%, respectively, of consolidated revenue for the three month periods ended March 31, 2018 and 2017.

American Airlines and one other customer each accounted for more than 10% of our consolidated accounts receivable as of March 31, 2018, and approximately 22% on a combined basis. One customer accounted for approximately 15% of consolidated accounts receivable as of December 31, 2017. Delta Air Lines one of our airline partners, accounted for approximately 13% and 21%, respectively, of consolidated accounts receivable as of March 31, 2018 and December 31, 2017.