Acquisition (Details) - USD ($) $ in Millions		9 Months Ended
Jan. 03, 2017	Sep. 30, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Goodwill		$ 2,309	$ 1,219
SquareTrade
Business Acquisition [Line Items]
Consideration transferred	$ 1,400
Goodwill	1,080	1,090
Commissions paid to retailers	70
Intangible assets	555
Prepaid contractual liability insurance policy premium expenses	201
Unearned premiums	373
Net deferred income tax liability	$ 140
Goodwill, period increase		14
Restricted cash		$ 30

Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Commissions Paid to Retailers

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Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Unearned Premiums

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of deferred tax liability attributable to taxable temporary differences assumed at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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