v3.10.0.1

Goodwill and Intangible Assets - Intangible Assets (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2017 | Dec. 31, 2017
Intangible assets: |  |  |  |  |
Gross Carrying Amount | $ 1,549 |  | $ 1,549 |  | $ 1,494
Accumulated Amortization | (1,443) |  | (1,443) |  | (1,425)
Intangible Assets, Net | 106 |  | 106 |  | 69
Amortization expense | 15 | $ 16 | 49 | $ 48 |
Customer lists and user base |  |  |  |  |
Intangible assets: |  |  |  |  |
Gross Carrying Amount | 522 |  | 522 |  | 458
Accumulated Amortization | (441) |  | (441) |  | (430)
Intangible Assets, Net | 81 |  | $ 81 |  | $ 28
Weighted Average Useful Life (Years) |  |  | 5 years |  | 5 years
Marketing related |  |  |  |  |
Intangible assets: |  |  |  |  |
Gross Carrying Amount | 588 |  | $ 588 |  | $ 607
Accumulated Amortization | (579) |  | (579) |  | (587)
Intangible Assets, Net | 9 |  | $ 9 |  | $ 20
Weighted Average Useful Life (Years) |  |  | 5 years |  | 5 years
Developed technologies |  |  |  |  |
Intangible assets: |  |  |  |  |
Gross Carrying Amount | 279 |  | $ 279 |  | $ 273
Accumulated Amortization | (268) |  | (268) |  | (258)
Intangible Assets, Net | 11 |  | $ 11 |  | $ 15
Weighted Average Useful Life (Years) |  |  | 3 years |  | 3 years
All other |  |  |  |  |
Intangible assets: |  |  |  |  |
Gross Carrying Amount | 160 |  | $ 160 |  | $ 156
Accumulated Amortization | (155) |  | (155) |  | (150)
Intangible Assets, Net | $ 5 |  | $ 5 |  | $ 6
Weighted Average Useful Life (Years) |  |  | 4 years |  | 4 years

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- Definition The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274 + Details
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- Definition Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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- Definition Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 928 -SubTopic 340 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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- Definition Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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