v3.8.0.1

Health Net - Commitments (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017 employee	Dec. 31, 2016 USD ($)	Mar. 24, 2016 USD ($)
Long term investments, California Organized Investment Network
Other Commitments [Line Items]
Commitment to undertaking			$ 30
Commitment to undertaking, term	5 years
Long Term Investment, service center in California
Other Commitments [Line Items]
Commitment to undertaking			200
Commitment to undertaking, term	10 years
Long term investment,improvement in enrollee health, locally based consumer assistance, and health care delivery system
Other Commitments [Line Items]
Commitment to undertaking			65
Long term investment,improvement in enrollee health
Other Commitments [Line Items]
Commitment to undertaking			10
Commitment to undertaking, term	5 years
Long term investment, support locally based consumer assistance
Other Commitments [Line Items]
Commitment to undertaking			5
Commitment to undertaking, term	5 years
Long term investment, strengthen the health care delivery system
Other Commitments [Line Items]
Commitment to undertaking			50
Commitment to undertaking, term	5 years
Long term investment, vehicles supporting California’s health care infrastructure
Other Commitments [Line Items]
Commitment to undertaking			$ 75
Selling, General and Administrative Expenses | Long term investment,improvement in enrollee health, locally based consumer assistance, and health care delivery system
Other Commitments [Line Items]
Commitment to undertaking, expensed		$ 61
Minimum | Long Term Investment, service center in California
Other Commitments [Line Items]
Commitment to undertaking, by employing (people) (at least) | employee	300

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- Definition

Other Commitment, Employees

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Other Commitment Expense

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Other Commitment, Term

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- Definition

Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

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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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