v3.8.0.1

Debt - Senior Notes (Details) - USD ($)	1 Months Ended
	Dec. 31, 2016	Nov. 30, 2016	Jun. 30, 2016	Dec. 31, 2017	Mar. 24, 2016	Feb. 29, 2016	Apr. 30, 2014
6.375% Senior notes due in 2017 | Senior Notes
Debt Instrument [Line Items]
Face amount	$ 400,000,000				$ 400,000,000
Interest rate stated, percentage	6.375%				6.375%
Repayment of senior note and premium for early redemption	$ 411,000,000
Loss on extinguishment of debt	$ 3,000,000
$425 million 5.75% Senior notes, due June 1, 2017 | Senior Notes
Debt Instrument [Line Items]
Face amount		$ 425,000,000
Interest rate stated, percentage		5.75%
Repayment of senior note and premium for early redemption		$ 447,000,000
Loss on extinguishment of debt		10,000,000
$1,200 million 4.75% Senior notes, due January 15, 2025 | Senior Notes
Debt Instrument [Line Items]
Face amount		$ 1,200,000,000		$ 1,200,000,000
Interest rate stated, percentage		4.75%		4.75%
$1,000 million 4.75% Senior notes, due May 15, 2022 | Senior Notes
Debt Instrument [Line Items]
Face amount				$ 1,000,000,000			$ 500,000,000
Interest rate stated, percentage			4.75%	4.75%			4.75%
Proceeds from issuance of debt			$ 500,000,000
Senior notes, effective yield			4.41%
5.625% Senior notes, due in 2021 | Senior Notes
Debt Instrument [Line Items]
Face amount				$ 1,400,000,000		$ 1,400,000,000
Interest rate stated, percentage				5.625%		5.625%
6.125% Senior notes, due in 2024 | Senior Notes
Debt Instrument [Line Items]
Face amount				$ 1,000,000,000		$ 1,000,000,000
Interest rate stated, percentage				6.125%		6.125%
Health Net, Inc.
Debt Instrument [Line Items]
Principal amount of debt assumed in acquisition					$ 418,000,000
Health Net, Inc. | Senior Notes
Debt Instrument [Line Items]
Principal amount of debt assumed in acquisition					$ 418,000,000
Interest rate swap
Debt Instrument [Line Items]
Derivative, notional amount				$ 2,700,000,000
Variable rate of swap, percentage				3.61%
Interest rate swap | $425 million 5.75% Senior notes, due June 1, 2017 | Senior Notes
Debt Instrument [Line Items]
Gain (loss) on contract termination		$ 2,000,000
Derivative, notional amount		$ 250,000,000
February 15, 2021
Debt Instrument [Line Items]
Derivative, notional amount				$ 600,000,000		$ 600,000,000
Variable rate of swap, percentage						4.22%
February 15, 2024
Debt Instrument [Line Items]
Derivative, notional amount				$ 1,000,000,000		$ 1,000,000,000
Variable rate of swap, percentage						4.44%

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- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
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The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

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