15. Segment Reporting

Operating segments are components of an enterprise for which separate financial information is available and regularly evaluated by the chief operating decision maker(s) of an enterprise. Operating income is the primary measure used by our chief operating decision maker to evaluate segment operating performance. We currently operate two primary business segments: (1) Pay-TV and (2) Wireless. See Note 1 for further information.

All other and eliminations primarily include intersegment eliminations related to intercompany debt and the related interest income and interest expense, which are eliminated in consolidation.

The total assets, revenue and operating income by segment were as follows:


	As of December 31,
	2017		2016
	(In thousands)
Total assets:
Pay-TV	$	28,353,581	$	26,980,276
Wireless		23,377,088		17,814,382
Eliminations		(21,956,903)		(16,880,366)
Total assets	$	29,773,766	$	27,914,292


					All
					Other &		Consolidated
	Pay-TV		Wireless		Eliminations		Total
	(In thousands)
Year Ended December 31, 2017
Total revenue	$	14,391,375	$	—	$	—	$	14,391,375
Depreciation and amortization		788,237		29,327		—		817,564
Operating income (loss)		1,759,130		(191,365)		—		1,567,765
Interest income		1,306,298		—		(1,265,292)		41,006
Interest expense, net of amounts capitalized		(1,068,231)		(260,233)		1,265,292		(63,172)
Other, net		104,482		6		—		104,488
Income tax (provision) benefit, net		(473,370)		988,690		—		515,320
Income (loss)		1,628,309		537,098		—		2,165,407

Year Ended December 31, 2016
Total revenue	$	15,212,302	$	—	$	—	$	15,212,302
Depreciation and amortization		877,342		43,860		—		921,202
Operating income (loss)		2,383,388		(64,127)		—		2,319,261
Interest income		1,006,243		3,745		(978,820)		31,168
Interest expense, net of amounts capitalized		(876,375)		(155,586)		978,820		(53,141)
Other, net		32,867		86,448		—		119,315
Income tax (provision) benefit, net		(934,024)		68,206		—		(865,818)
Income (loss)		1,612,099		(61,314)		—		1,550,785

Year Ended December 31, 2015
Total revenue	$	15,225,097	$	396	$	—	$	15,225,493
Depreciation and amortization		919,058		44,299		—		963,357
Operating income (loss)		2,133,947		(705,575)		—		1,428,372
Interest income		859,608		9,434		(849,516)		19,526
Interest expense, net of amounts capitalized		(844,320)		(499,277)		849,516		(494,081)
Other, net		85,496		195,883		—		281,379
Income tax (provision) benefit, net		(785,642)		392,472		—		(393,170)
Income (loss)		1,449,089		(607,063)		—		842,026

Geographic Information. Revenue is attributed to geographic regions based upon the location where the goods and services are provided. All subscriber-related revenue was derived from the United States. Substantially all of our long-lived assets reside in the United States.

The following table summarizes revenue by geographic region:


	For the Years Ended December 31,
Revenue:	2017		2016		2015
	(In thousands)
United States	$	14,351,558	$	15,111,832	$	15,090,923
Canada and Mexico		39,817		100,470		134,570
Total revenue	$	14,391,375	$	15,212,302	$	15,225,493