Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Millions |
1 Months Ended | 12 Months Ended | |||
|---|---|---|---|---|---|
Mar. 24, 2016 |
Jan. 31, 2016 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Class of Stock [Line Items] | |||||
| Preferred stock, shares authorized (in shares) | 10,000,000 | 10,000,000 | |||
| Preferred stock, par value (in usd per share) | $ 0.001 | $ 0.001 | |||
| Preferred stock, shares outstanding (in shares) | 0 | 0 | |||
| Common stock, shares authorized to repurchase | 8,000,000 | ||||
| Remaining number of shares available to be repurchased | 3,335,000 | ||||
| Treasury stock, shares, acquired | 727,000 | 1,078,000 | |||
| Payments for repurchase of common stock (in usd) | $ 65 | $ 63 | $ 53 | ||
| Percentage of voting interests acquired | 19.00% | ||||
| Stock issued during period, shares, new issues | 1,144,000 | ||||
| Health Net, Inc. | |||||
| Class of Stock [Line Items] | |||||
| Common stock issued for acquisitions (in shares) | 48,449,000 | ||||
| Business acquisition, consideration transferred, Centene common stock issued, value | $ 3,038 | ||||
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- Definition Percentage of voting equity interests acquired at the acquisition date in the business combination. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition 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. No definition available.
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- Definition The cash outflow to reacquire common stock during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of shares of stock issued during the period pursuant to acquisitions. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of new stock issued during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan. No definition available.
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- Definition The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan. No definition available.
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- Definition Number of shares that have been repurchased during the period and are being held in treasury. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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