[Line Items] for Accounting Policies [Table]

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- Definition

Land-use rights

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for advertising of the entity's goods and services. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Period between issuance and maturity of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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- Definition

Amount of lessee's right to use underlying asset under operating lease.

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- Definition

Amount of acquisition of long-lived, 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, furniture and fixtures, and computer equipment.

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No definition available.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Narrative) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($) segment	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Jan. 01, 2019 USD ($)	Jan. 01, 2018 USD ($)	Jan. 01, 2017 USD ($)
Accounting Policies [Line Items]
Land-use rights		$ 47
One-time adjustment to retained earnings at adoption of ASC 606					$ 189	$ 280
Accrued performance advertising liabilities	$ 333	313
Accrued compensation liabilities	$ 344	348
Number of reportable segments \| segment	1
Operating lease assets	$ 620	0
Operating lease liability	623
Current operating lease liabilities	161
Capitalized software
Accounting Policies [Line Items]
Additions to capitalized website development	106	$ 97	$ 80
Accounting Standards Update 2016-02
Accounting Policies [Line Items]
Operating lease assets				$ 646
Operating lease liability				646
Current operating lease liabilities				$ 152
Accounting Standards Update 2014-09
Accounting Policies [Line Items]
One-time adjustment to retained earnings at adoption of ASC 606					189
Retained Earnings
Accounting Policies [Line Items]
One-time adjustment to retained earnings at adoption of ASC 606					430	$ 271
Retained Earnings \| Accounting Standards Update 2014-09
Accounting Policies [Line Items]
One-time adjustment to retained earnings at adoption of ASC 606	$ 0				$ (32)
Minimum \| Capitalized software
Accounting Policies [Line Items]
Estimated useful life	2 years
Maximum
Accounting Policies [Line Items]
Debt Securities, Available-for-sale, Term	5 years
Renewal Term	9 years
Maximum \| Capitalized software
Accounting Policies [Line Items]
Estimated useful life	5 years