Acquisitions (Narrative) (Details) - USD ($) $ in Millions |
12 Months Ended | ||||
---|---|---|---|---|---|
Nov. 30, 2016 |
Jun. 27, 2016 |
Dec. 31, 2018 |
Dec. 31, 2016 |
Dec. 31, 2017 |
|
Business Acquisition [Line Items] | |||||
Net purchase price | $ 101 | ||||
Goodwill | $ 476 | $ 471 | $ 476 | ||
Average useful life for each class of definite lived intangible asset recorded for acquisitions | 5 years | ||||
OneGuard [Member] | |||||
Business Acquisition [Line Items] | |||||
Net purchase price | $ 61 | ||||
Goodwill | 57 | ||||
Other intangibles related to acquisitions | $ 15 | ||||
Landmark [Member] | |||||
Business Acquisition [Line Items] | |||||
Net purchase price | $ 39 | ||||
Goodwill | 37 | ||||
Other intangibles related to acquisitions | $ 13 |