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Affordable Care Act, Premium Stabilization Program, Risk Corridor, Receivable Not Recognized

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Affordable Care Act, Premium Stabilization Program, Risk Corridor, Receivable Not Recognized, Current Year

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Affordable Care Act, Premium Stabilization Program, Risk Corridor, Receivable Not Recognized, Prior Years

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Health Care Reform, Premium Deficiency Reserve

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Investments, Average Maturity Period

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Medical administrative costs.

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Medical Premium Liability Due to Agency

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Medical Premiums Liability, Medical Care Costs Threshold

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Percentage of additional incremental revenue earned.

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Amount of deferred revenue recognized for transactions arising during the current reporting period. Deferred revenue is a liability as of the balance sheet date related to a revenue producing activity for which revenue has not yet been recognized. Generally, an Entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of insurance premium revenue recognized.

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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 revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Significant Accounting Policies (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended			24 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Final maturities of investments									10 years
Average maturity of investments									3 years
Amounts due government agencies	$ 1,202				$ 729				$ 1,202	$ 729		$ 729
Premium revenue	4,177	$ 4,191	$ 4,029	$ 3,995	3,589	$ 3,377	$ 3,304	$ 2,971	16,392	13,241	$ 9,023
Accounts payable	385				362				385	362		362
Revenues									17,782	14,178	9,667
Risk transfer payment above estimate									40
Unrecorded receivable for Marketplace risk corridor	142								142
Unrecorded receivable for Marketplace risk corridor, prior year	52								52
Unrecorded receivable for Marketplace risk corridor, current year	90								90
Medical administrative costs									488	398	263
Premium deficiency recorded	30								30
Health Plans
Property, Plant and Equipment [Line Items]
Premium revenue									16,392	13,241	9,023
Revenues									17,234	13,917	9,449
Medicaid Expansion
Property, Plant and Equipment [Line Items]
Amounts due government agencies	244				208				244	208		208
Florida \| Health Plans
Property, Plant and Equipment [Line Items]
Premium revenue									1,926	1,199	439
New Mexico \| Health Plans
Property, Plant and Equipment [Line Items]
Premium revenue									1,304	1,237	1,076
Texas \| Health Plans
Property, Plant and Equipment [Line Items]
Premium revenue									2,454	1,961	$ 1,318
Texas \| Quality Incentives
Property, Plant and Equipment [Line Items]
Deferred revenue recognized during period			$ 51
Deferred revenue for services provided												44
California Department of Healthcare Services
Property, Plant and Equipment [Line Items]
Premium revenue									68
California Department of Healthcare Services \| Claims for services prior to 2016
Property, Plant and Equipment [Line Items]
Premium revenue									35
New Mexico Human Services Department
Property, Plant and Equipment [Line Items]
Accounts payable	145								145
Adjustment to Previously Recognized Revenue \| Florida
Property, Plant and Equipment [Line Items]
Revenues				$ 18
Adjustment to Previously Recognized Revenue \| New Mexico Human Services Department
Property, Plant and Equipment [Line Items]
Premium revenue									(45)
Adjustment to Previously Recognized Revenue \| New Mexico Human Services Department \| Claims for services prior to 2016
Property, Plant and Equipment [Line Items]
Premium revenue									(29)
Medical Premium Liability Due to Agency
Property, Plant and Equipment [Line Items]
Medical premium liability based on medical costs threshold	$ 272				$ 214				$ 272	$ 214		$ 214
Minimum \| California, Illinois, New Mexico, Ohio, South Carolina, Texas, Washington, and Wisconsin
Property, Plant and Equipment [Line Items]
Percentage of additional incremental revenue earned									1.00%
Maximum
Property, Plant and Equipment [Line Items]
Final maturities of investments									10 years
Average maturity of investments									3 years
Maximum \| California, Illinois, New Mexico, Ohio, South Carolina, Texas, Washington, and Wisconsin
Property, Plant and Equipment [Line Items]
Percentage of additional incremental revenue earned									3.00%