Operating Segments

3 Months Ended

Mar. 31, 2018

Segment Reporting Disclosure [Text Block]

Operating Segments

The Company's operating segments are (1) Towers and (2) Fiber. The Towers segment provides access, including space or capacity, to the Company's approximately 40,000 towers geographically dispersed throughout the U.S. The Towers segment also reflects certain network services relating to the Company's towers, consisting of site development services and installation services. The Fiber segment provides access, including space or capacity, to the Company's approximately 60,000 route miles of fiber primarily supporting small cell networks and fiber solutions.

The measurements of profit or loss used by the Company's chief operating decision maker to evaluate the results of operations of its operating segments are (1) segment site rental gross margin, (2) segment network services and other gross margin and (3) segment operating profit. The Company defines segment site rental gross margin as segment site rental revenues less segment site rental cost of operations, which excludes stock-based compensation expense and prepaid lease purchase price adjustments recorded in consolidated cost of operations. The Company defines segment network services and other gross margin as segment network services and other revenues less segment network services and other cost of operations, which excludes stock-based compensation expense recorded in consolidated cost of operations. The Company defines segment operating profit as segment site rental gross margin plus segment network services and other gross margin, less general and administrative expenses attributable to the respective segment.

Costs that are directly attributable to Towers and Fiber are assigned to those respective segments. The "Other" column (1) represents amounts excluded from specific segments, such as restructuring charges (credits), asset write-down charges, acquisition and integration costs, depreciation, amortization and accretion, amortization of prepaid lease purchase price adjustments, interest expense and amortization of deferred financing costs, gains (losses) on retirement of long-term obligations, net gain (loss) on interest rate swaps, gains (losses) on foreign currency swaps, impairment of available-for-sale securities, interest income, other income (expense), cumulative effect of a change in accounting principle, income (loss) from discontinued operations, and stock-based compensation expense, and (2) reconciles segment operating profit to income (loss) before income taxes, as the amounts are not utilized in assessing each segment’s performance. The "Other" total assets balance includes corporate assets such as cash and cash equivalents which have not been allocated to specific segments. There are no significant revenues resulting from transactions between the Company's operating segments.



	Three Months Ended March 31, 2018								Three Months Ended March 31, 2017
	Towers		Fiber		Other		Consolidated Total		Towers		Fiber		Other		Consolidated Total
Segment site rental revenues	$	764	$	389			$	1,153	$	717	$	140			$	857
Segment network services and other revenues	142		4				146		150		9				159
Segment revenues	906		393				1,299		867		149				1,016
Segment site rental cost of operations	211		126				337		209		47				256
Segment network services and other cost of operations	82		2				84		89		8				97
Segment cost of operations^(a)	293		128				421		298		55				353
Segment site rental gross margin	553		263				816		508		93				601
Segment network services and other gross margin	60		2				62		61		1				62
Segment general and administrative expenses^(a)	26		43				69		24		18				42
Segment operating profit (loss)	587		222				809		545		76				621
Other general and administrative expenses^(a)					$	46	46						$	39	39
Stock-based compensation expense					26		26						25		25
Depreciation, amortization and accretion					374		374						289		289
Interest expense and amortization of deferred financing costs					160		160						134		134
Other income (expenses) to reconcile to income (loss) before income taxes^(b)					85		85						11		11
Income (loss) before income taxes							$	118							$	123
Capital expenditures	$	96	$	262	$	12	$	370	$	101	$	154	$	7	$	262
Total assets (at period end)	$	17,868	$	13,883	$	499	$	32,250	$	18,255	$	5,054	$	468	$	23,777

(a)

Segment cost of operations excludes (1) stock-based compensation expense of $7 million and $5 million for the three months ended March 31, 2018 and 2017, respectively, and (2) prepaid lease purchase price adjustments of $5 million for both of the three months ended March 31, 2018 and 2017. General and administrative expenses exclude stock-based compensation expense of $19 million and $20 million for the three months ended March 31, 2018 and 2017, respectively.


(b)	See condensed consolidated statement of operations for further information.