Property and Equipment (Detail) - USD ($)	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment
Property and equipment, gross	$ 7,819,000,000	$ 5,784,000,000
Less: Accumulated depreciation	(2,132,000,000)	(1,817,000,000)
Property and equipment, net	5,687,000,000	3,967,000,000
Depreciation expense	1,220,000,000	923,000,000	$ 857,000,000
Assets acquired under capital lease agreements	287,000,000	700,000,000
Accumulated depreciation of property and equipment acquired under capital leases	71,000,000	425,000,000
Interest costs capitalized	0	0
Land
Property, Plant and Equipment
Property and equipment, gross	596,000,000	153,000,000
Buildings
Property, Plant and Equipment
Property and equipment, gross	2,273,000,000	1,420,000,000
Leasehold improvements
Property, Plant and Equipment
Property and equipment, gross	447,000,000	304,000,000
Network equipment
Property, Plant and Equipment
Property and equipment, gross	3,633,000,000	3,020,000,000
Computer software, office equipment and other
Property, Plant and Equipment
Property and equipment, gross	248,000,000	149,000,000
Construction in progress
Property, Plant and Equipment
Property and equipment, gross	$ 622,000,000	$ 738,000,000

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.14)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.

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The total charge for the use of long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6455314&loc=d3e45014-112735

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of interest capitalized during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Allowance for Funds Used during Construction
-URI http://asc.fasb.org/extlink&oid=6504829

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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