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Percentage of Net Accounts Receivable

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Percentage of Net Revenues

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Receivables due from patients as a percentage of consolidated net accounts receivable.

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for contractual rent under lease arrangements.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI) and investment in equity security without readily determinable fair value.

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Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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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.

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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

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

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2019
Summary of Significant Accounting Policies [Line Items]
Equity method investments carrying value	$ 482,000,000				$ 436,000,000				$ 482,000,000	$ 436,000,000
Percentage of net revenues									100.00%	100.00%	100.00%
Share of equity earnings from investments in affiliates									$ 57,000,000	$ 44,000,000	$ 35,000,000
Percentage of net accounts receivable	100.00%				100.00%				100.00%	100.00%
Percentage of receivables due from patients	20.00%				20.00%				20.00%	20.00%
Operating income (loss)									$ 1,231,000,000	$ 1,101,000,000	1,165,000,000
Net income	$ 265,000,000	$ 226,000,000	$ 239,000,000	$ 176,000,000	$ 139,000,000	$ 227,000,000	$ 233,000,000	$ 189,000,000	906,000,000	788,000,000	824,000,000
Trading equity securities gain or (loss)									10,000,000	(2,000,000)	8,000,000
Impairment charges									0	0	$ 0
Equity securities, FV-NI and without readily determinable fair value	25,000,000				10,000,000				25,000,000	10,000,000
Available-for-sale debt securities	12,000,000				0				12,000,000	0
Operating lease right-of-use assets	518,000,000				0				518,000,000	0		$ 500,000,000
Operating lease, liability	558,000,000								558,000,000			550,000,000
Accrued rent												$ 50,000,000
Other Assets
Summary of Significant Accounting Policies [Line Items]
Trading securities, equity	$ 59,000,000								$ 59,000,000
Trading securities, equity					$ 53,000,000					$ 53,000,000
DIS business
Summary of Significant Accounting Policies [Line Items]
Percentage of net revenues									96.00%	96.00%	96.00%
Percentage of net accounts receivable	95.00%				96.00%				95.00%	96.00%
Operating income (loss)									$ 1,298,000,000	$ 1,235,000,000	$ 1,313,000,000
DIS business \| Government payers
Summary of Significant Accounting Policies [Line Items]
Percentage of net revenues									15.00%	16.00%	17.00%
Percentage of net accounts receivable	11.00%				13.00%				11.00%	13.00%
Minimum
Summary of Significant Accounting Policies [Line Items]
Equity method investment, ownership percentage	20.00%								20.00%
Finite-lived intangible asset, useful life									5 years
Minimum \| Laboratory Equipment and Furniture and Fixtures
Summary of Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life									5 years
Minimum \| Software and Software Development Costs
Summary of Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life									5 years
Minimum \| DIS business
Summary of Significant Accounting Policies [Line Items]
Percentage of net revenues									95.00%	95.00%	95.00%
Maximum
Summary of Significant Accounting Policies [Line Items]
Equity method investment, ownership percentage	49.00%								49.00%
Finite-lived intangible asset, useful life									20 years
Maximum \| Building and Building Improvements
Summary of Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life									31 years 6 months
Maximum \| Laboratory Equipment and Furniture and Fixtures
Summary of Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life									12 years
Maximum \| Software and Software Development Costs
Summary of Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life									10 years