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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