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Gain Contingency, Recovery Sought

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- Definition

Number Of Matters Related To Notice Of Non-Intervention

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Percentage Of Total Premium And Services Revenues

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77896938&loc=d3e25336-109308

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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COMMITMENTS, GUARANTEES AND CONTINGENCIES - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2017 USD ($)	Nov. 02, 2017 USD ($)	May 01, 2014 matter	Jan. 06, 2012 provider
Loss Contingencies [Line Items]
Purchase obligations in 2018	$ 226
Purchase obligations in 2019	150
Purchase obligations in 2020	38
Purchase obligations in 2021	8
Purchase obligations thereafter	$ 7
Number of medical providers questioned (one or more) \| provider				1
Number of matters related to notice of non-intervention \| matter			1
Litigation recoveries sought		$ 611
Tricare South Region Contract
Loss Contingencies [Line Items]
Contract term years	5 years
Tricare East Region Contract
Loss Contingencies [Line Items]
Contract term years	5 years
Total Medicare
Loss Contingencies [Line Items]
Percentage of premiums and services revenue	78.00%
Military services
Loss Contingencies [Line Items]
Percentage of premiums and services revenue	1.00%
Medicaid
Loss Contingencies [Line Items]
Percentage of premiums and services revenue	5.00%