Centene (CNC) 10-Q 27 Oct 20 2020 Q3 Quarterly report Financial data

Cover

Cover - shares	9 Months Ended
	Sep. 30, 2020	Oct. 16, 2020
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2020
Document Transition Report	false
Entity File Number	001-31826
Entity Registrant Name	CENTENE CORPORATION
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	42-1406317
Entity Address, Address Line One	7700 Forsyth Boulevard
Entity Address, City or Town	St. Louis,
Entity Address, State or Province	MO
Entity Address, Postal Zip Code	63105
City Area Code	314
Local Phone Number	725-4477
Title of 12(b) Security	Common Stock $0.001 Par Value
Trading Symbol	CNC
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		579,797,682
Entity Central Index Key	0001071739
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3
Amendment Flag	false

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 12,198	$ 12,123
Premium and trade receivables	11,670	6,247
Short-term investments	1,497	863
Other current assets	1,910	1,090
Total current assets	27,275	20,323
Long-term investments	9,859	7,717
Restricted deposits	1,055	658
Property, software and equipment, net	2,669	2,121
Goodwill	17,964	6,863
Intangible assets, net	8,130	2,063
Other long-term assets	1,412	1,249
Total assets	68,364	40,994
Current liabilities:
Medical claims liability	12,899	7,473
Accounts payable and accrued expenses	7,102	4,164
Return of premium payable	1,123	824
Unearned revenue	582	383
Current portion of long-term debt	89	88
Total current liabilities	21,795	12,932
Long-term debt	16,737	13,638
Other long-term liabilities	3,953	1,732
Total liabilities	42,485	28,302
Commitments and contingencies
Redeemable noncontrolling interests	36	33
Stockholders’ equity:
Preferred stock, $0.001 par value; authorized 10,000 shares; no shares issued or outstanding at September 30, 2020 and December 31, 2019	0	0
Common stock, $0.001 par value; authorized 800,000 shares; 595,622 issued and 579,726 outstanding at September 30, 2020, and 421,508 issued and 415,048 outstanding at December 31, 2019	0	0
Additional paid-in capital	19,390	7,647
Accumulated other comprehensive earnings	293	134
Retained earnings	6,804	4,984
Treasury stock, at cost (15,896 and 6,460 shares, respectively)	(762)	(214)
Total Centene stockholders’ equity	25,725	12,551
Nonredeemable Noncontrolling interest	118	108
Total stockholders’ equity	25,843	12,659
Total liabilities, redeemable noncontrolling interests and stockholders’ equity	$ 68,364	$ 40,994

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Sep. 30, 2020	Dec. 31, 2019
Stockholders' equity
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	800,000,000	800,000,000
Common stock, shares issued (in shares)	595,622,000	421,508,000
Common stock, shares outstanding (in shares)	579,726,000	415,048,000
Treasury stock (in shares)	15,896,000	6,460,000

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenues:
Premium and service revenues	$ 27,459	$ 18,215	$ 77,355	$ 52,352
Premium tax and health insurer fee	1,631	761	5,472	3,424
Total revenues	29,090	18,976	82,827	55,776
Expenses:
Medical costs	22,932	15,406	63,659	43,642
Cost of services	861	619	2,519	1,778
Selling, general and administrative expenses	2,507	1,617	7,146	4,800
Amortization of acquired intangible assets	164	65	527	194
Premium tax expense	1,389	822	4,737	3,587
Health insurer fee expense	376	0	1,100	0
Impairment	0	271	72	271
Total operating expenses	28,229	18,800	79,760	54,272
Earnings from operations	861	176	3,067	1,504
Other income (expense):
Investment and other income	95	98	375	317
Debt extinguishment costs	0	0	(44)	0
Interest expense	(184)	(99)	(551)	(299)
Earnings from operations, before income tax expense	772	175	2,847	1,522
Income tax expense	207	79	1,034	415
Net earnings	565	96	1,813	1,107
Loss (earnings) attributable to noncontrolling interests	3	(1)	7	5
Net earnings attributable to Centene Corporation	$ 568	$ 95	$ 1,820	$ 1,112
Net earnings per common share attributable to Centene Corporation:
Basic earnings per common share (in dollars per share)	$ 0.98	$ 0.23	$ 3.21	$ 2.69
Diluted earnings per common share (in dollars per share)	$ 0.97	$ 0.23	$ 3.16	$ 2.65
Weighted average number of common shares outstanding:
Basic (in shares)	579,510	413,616	567,586	413,302
Diluted (in shares)	587,971	419,956	575,732	419,700
Premium
Revenues:
Premium and service revenues	$ 26,537	$ 17,472	$ 74,496	$ 50,229
Service
Revenues:
Premium and service revenues	$ 922	$ 743	$ 2,859	$ 2,123

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Comprehensive Income [Abstract]
Net earnings	$ 565	$ 96	$ 1,813	$ 1,107
Reclassification adjustment, net of tax	0	(1)	1	0
Change in unrealized gain on investments, net of tax	38	34	152	208
Defined benefit pension plan net gain, net of tax	0	0	2	0
Foreign currency translation adjustments	10	(7)	4	(7)
Other comprehensive earnings	48	26	159	201
Comprehensive earnings	613	122	1,972	1,308
Comprehensive loss (earnings) attributable to noncontrolling interests	3	(1)	7	5
Comprehensive earnings attributable to Centene Corporation	$ 616	$ 121	$ 1,979	$ 1,313

CONSOLIDATED STATEMENTS OF STOC

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Millions	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Earnings (Loss)	Retained Earnings	Treasury Stock	Non-redeemable Non- controlling Interest
Balance (in shares) at Dec. 31, 2018		417,695
Balance at Dec. 31, 2018	$ 11,013	$ 0	$ 7,449	$ (56)	$ 3,663	$ (139)	$ 96
Treasury stock (in shares) at Dec. 31, 2018						5,217
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings (loss)	520				522		(2)
Other comprehensive (loss) earnings, net of tax	94			94
Common stock issued for employee benefit plans (in shares)		1,363
Common stock issued for employee benefit plans	4		4
Common stock repurchases (in shares)						(536)
Common stock repurchases	(35)					$ (35)
Stock compensation expense	38		38
Balance (in shares) at Mar. 31, 2019		419,058
Balance at Mar. 31, 2019	11,634	$ 0	7,491	38	4,185	$ (174)	94
Treasury stock (in shares) at Mar. 31, 2019						5,753
Balance (in shares) at Dec. 31, 2018		417,695
Balance at Dec. 31, 2018	11,013	$ 0	7,449	(56)	3,663	$ (139)	96
Treasury stock (in shares) at Dec. 31, 2018						5,217
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive (loss) earnings, net of tax	201
Balance (in shares) at Sep. 30, 2019		419,667
Balance at Sep. 30, 2019	12,405	$ 0	7,571	145	4,775	$ (180)	94
Treasury stock (in shares) at Sep. 30, 2019						5,874
Balance (in shares) at Mar. 31, 2019		419,058
Balance at Mar. 31, 2019	11,634	$ 0	7,491	38	4,185	$ (174)	94
Treasury stock (in shares) at Mar. 31, 2019						5,753
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings (loss)	495				495
Other comprehensive (loss) earnings, net of tax	81			81
Common stock issued for employee benefit plans (in shares)		261
Common stock issued for employee benefit plans	6		6
Common stock repurchases (in shares)						(39)
Common stock repurchases	(2)					$ (2)
Stock compensation expense	34		34
Balance (in shares) at Jun. 30, 2019		419,319
Balance at Jun. 30, 2019	12,248	$ 0	7,531	119	4,680	$ (176)	94
Treasury stock (in shares) at Jun. 30, 2019						5,792
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings (loss)	95				95
Other comprehensive (loss) earnings, net of tax	26			26
Common stock issued for employee benefit plans (in shares)		348
Common stock issued for employee benefit plans	6		6
Common stock repurchases (in shares)						(82)
Common stock repurchases	(4)					$ (4)
Stock compensation expense	34		34
Balance (in shares) at Sep. 30, 2019		419,667
Balance at Sep. 30, 2019	$ 12,405	$ 0	7,571	145	4,775	$ (180)	94
Treasury stock (in shares) at Sep. 30, 2019						5,874
Balance (in shares) at Dec. 31, 2019	415,048	421,508
Balance at Dec. 31, 2019	$ 12,659	$ 0	7,647	134	4,984	$ (214)	108
Treasury stock (in shares) at Dec. 31, 2019	6,460					6,460
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings (loss)	$ 43				46		(3)
Other comprehensive (loss) earnings, net of tax	(139)			(139)
Common stock issued for acquisitions (in shares)		171,225
Common stock issued for acquisitions	11,526		11,526
Common stock issued for employee benefit plans (in shares)		2,448
Common stock issued for employee benefit plans	5		5
Common stock repurchases (in shares)		(291)				(9,308)
Common stock repurchases	(558)		(17)			$ (541)
Stock compensation expense	117		117
Contribution from noncontrolling interest	2						2
Other	1		1				0
Balance (in shares) at Mar. 31, 2020		594,890
Balance at Mar. 31, 2020	$ 23,656	$ 0	19,279	(5)	5,030	$ (755)	107
Treasury stock (in shares) at Mar. 31, 2020						15,768
Balance (in shares) at Dec. 31, 2019	415,048	421,508
Balance at Dec. 31, 2019	$ 12,659	$ 0	7,647	134	4,984	$ (214)	108
Treasury stock (in shares) at Dec. 31, 2019	6,460					6,460
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive (loss) earnings, net of tax	$ 159
Balance (in shares) at Sep. 30, 2020	579,726	595,622
Balance at Sep. 30, 2020	$ 25,843	$ 0	19,390	293	6,804	$ (762)	118
Treasury stock (in shares) at Sep. 30, 2020	15,896					15,896
Balance (in shares) at Mar. 31, 2020		594,890
Balance at Mar. 31, 2020	$ 23,656	$ 0	19,279	(5)	5,030	$ (755)	107
Treasury stock (in shares) at Mar. 31, 2020						15,768
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings (loss)	1,200				1,206		(6)
Other comprehensive (loss) earnings, net of tax	250			250
Common stock issued for employee benefit plans (in shares)		269
Common stock issued for employee benefit plans	7		7
Common stock repurchases (in shares)		1				(47)
Common stock repurchases	(3)					$ (3)
Stock compensation expense	47		47
Contribution from noncontrolling interest	15						15
Balance (in shares) at Jun. 30, 2020		595,160
Balance at Jun. 30, 2020	25,172	$ 0	19,333	245	6,236	$ (758)	116
Treasury stock (in shares) at Jun. 30, 2020						15,815
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings (loss)	562				568		(6)
Other comprehensive (loss) earnings, net of tax	48			48
Common stock issued for employee benefit plans (in shares)		531
Common stock issued for employee benefit plans	8		8
Common stock repurchases (in shares)		(69)				(81)
Common stock repurchases	(9)		(5)			$ (4)
Stock compensation expense	54		54
Contribution from noncontrolling interest	$ 8						8
Balance (in shares) at Sep. 30, 2020	579,726	595,622
Balance at Sep. 30, 2020	$ 25,843	$ 0	$ 19,390	$ 293	$ 6,804	$ (762)	$ 118
Treasury stock (in shares) at Sep. 30, 2020	15,896					15,896

CONSOLIDATED STATEMENTS OF ST_2

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Parenthetical) - USD ($) $ in Millions	3 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2018
Par value (in dollars per share)	$ 0.001						$ 0.001
Other comprehensive (loss) earnings, tax	$ 13	$ 76	$ (40)	$ 11	$ 25	$ 30
Common Stock
Par value (in dollars per share)	$ 0.001	$ 0.001	$ 0.001	$ 0.001	$ 0.001	$ 0.001	0.001	$ 0.001
Treasury Stock
Par value (in dollars per share)	$ 0.001	$ 0.001	$ 0.001	$ 0.001	$ 0.001	$ 0.001	$ 0.001	$ 0.001

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Cash flows from operating activities:
Net earnings	$ 1,813	$ 1,107
Adjustments to reconcile net earnings to net cash provided by operating activities
Depreciation and amortization	916	475
Stock compensation expense	218	106
Impairment	72	271
Loss on debt extinguishment	44	0
Deferred income taxes	(154)	(75)
Gain on divestiture	(104)	0
Changes in assets and liabilities
Premium and trade receivables	(1,640)	(319)
Other assets	185	(14)
Medical claims liabilities	1,563	1,091
Unearned revenue	(212)	(10)
Accounts payable and accrued expenses	(861)	(552)
Other long-term liabilities	663	68
Other operating activities, net	19	(14)
Net cash provided by operating activities	2,522	2,134
Cash flows from investing activities:
Capital expenditures	(663)	(530)
Purchases of investments	(2,911)	(2,074)
Sales and maturities of investments	3,408	1,247
Acquisitions, net of cash acquired	(3,000)	(31)
Divestiture proceeds, net of divested cash	466	0
Net cash used in investing activities	(2,700)	(1,388)
Cash flows from financing activities:
Proceeds from long-term debt	2,687	12,456
Payments of long-term debt	(1,654)	(12,293)
Common stock repurchases	(570)	(41)
Payments for debt extinguishment	(21)	0
Debt issuance costs	(94)	(6)
Other financing activities, net	35	12
Net cash provided by financing activities	383	128
Effect of exchange rate changes on cash, cash equivalents, and restricted cash	8	4
Net increase in cash, cash equivalents and restricted cash and cash equivalents	213	878
Cash, cash equivalents, and restricted cash and cash equivalents, beginning of period	12,131	5,350
Cash, cash equivalents, and restricted cash and cash equivalents, end of period	12,344	6,228
Supplemental disclosures of cash flow information:
Interest paid	479	213
Income taxes paid	920	511
Equity issued in connection with acquisitions	11,526	0
The following table provides a reconciliation of cash, cash equivalents, and restricted cash and cash equivalents reported within the Consolidated Balance Sheets to the totals above:
Cash and cash equivalents	12,198	6,215
Restricted cash and cash equivalents, included in restricted deposits	146	13
Total cash, cash equivalents, and restricted cash and cash equivalents	$ 12,344	$ 6,228

Organization and Operations

Organization and Operations	9 Months Ended
	Sep. 30, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Operations	Organization and Operations Basis of Presentation The accompanying interim financial statements have been prepared under the presumption that users of the interim financial information have either read or have access to the audited financial statements included in the Form 10-K for the fiscal year ended December 31, 2019. The unaudited interim financial statements herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission. Accordingly, footnote disclosures that would substantially duplicate the disclosures contained in the December 31, 2019 audited financial statements have been omitted from these interim financial statements, where appropriate. In the opinion of management, these financial statements reflect all adjustments, consisting only of normal recurring adjustments, which are necessary for a fair presentation of the results of the interim periods presented. Certain 2019 amounts in the consolidated financial statements and notes to the consolidated financial statements have been reclassified to conform to the 2020 presentation. These reclassifications have no effect on net earnings or stockholders’ equity as previously reported. On January 23, 2020, the Company acquired all of the issued and outstanding shares of WellCare Health Plans, Inc. (WellCare) (the WellCare Acquisition). The acquisition was accounted for as a business combination. See Note 2. Acquisitions for further details. Recently Adopted Accounting Guidance In June 2016, the Financial Accounting Standards Board (FASB) issued an Accounting Standards Update (ASU) which changes how entities measure credit losses for most financial assets and certain other investments that are not measured at fair value through net income. The ASU is intended to improve financial reporting by requiring timelier recording of credit losses on loans and other financial instruments held by financial institutions and other organizations. The amended guidance requires the measurement of all expected credit losses for financial assets (or groups of financial assets) and available for sale debt securities held at the reporting date over the remaining life based on historical experience, current conditions, and reasonable and supportable forecasts. The guidance is effective for annual and interim periods beginning after December 15, 2019. The Company adopted the new guidance in the first quarter of 2020. The majority of the Company’s receivables and other financial instruments are with government entities and, therefore, the adoption did not have a material impact on its receivables and other financial instruments. The Company evaluated its investment portfolio under the new available-for-sale debt securities impairment model guidance. The vast majority of the Company’s investment portfolio are low risk, investment grade securities. The impact of the Company’s evaluation of the investment portfolio resulted in an immaterial decrease to retained earnings at January 1, 2020. The Company evaluates available-for-sale debt securities on a regular basis and records an allowance for credit losses, if necessary. The comparative information has not been restated and continues to be reported under the accounting standards in effect for those periods. The new guidance did not have a material impact on the Company’s consolidated financial position, results of operations or cash flows. In August 2018, the FASB issued an ASU which aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal use software license). The accounting for the service element of a hosting arrangement that is a service contract is not affected by the amendments in this update. The amendments in this ASU require an entity that is the customer in a hosting arrangement to follow the guidance on internal-use software to determine which implementation costs to capitalize and which costs to expense. The standard also requires an entity that is the customer to expense the capitalized implementation costs of a hosting arrangement over the term of the hosting arrangement. The new guidance requires an entity to present the expense related to the capitalized implementation costs in the same line item in the statement of income as the fees associated with the hosting element of the arrangement and classify payments for capitalized implementation costs in the statement of cash flows in the same manner as payments made for fees associated with the hosting element. The entity is also required to present the capitalized implementation costs in the statement of financial position in the same line item that a prepayment for the fees of the associated hosting arrangement would be presented. The guidance is effective for annual and interim periods beginning after December 15, 2019. The Company adopted the new guidance in the first quarter of 2020. The new guidance did not have a material impact on the Company’s consolidated financial position, results of operations or cash flows. Recent Accounting Guidance Not Yet Adopted In December 2019, the FASB issued an ASU which simplifies the accounting for income taxes by removing certain exceptions to the general principles in ASC Topic 740. The ASU also clarifies and amends certain areas of ASC Topic 740 to improve consistent application of and simplify the generally accepted accounting principles within Topic 740. The guidance is effective for annual and interim periods beginning after December 15, 2020. The Company is continuing to evaluate the potential impact of the ASU on the Company’s consolidated financial position, results of operations and cash flows but expects the impact to be immaterial.

Acquisitions

Acquisitions	9 Months Ended
	Sep. 30, 2020
Business Combinations [Abstract]
Acquisitions	Acquisitions WellCare Acquisition On January 23, 2020, the Company acquired all of the issued and outstanding shares of WellCare. The transaction was valued at $19,555 million, including the assumption of debt. The WellCare Acquisition brings a high-quality Medicare platform and further extends the Company’s robust Medicaid offerings. The WellCare Acquisition also enables the Company to provide access to more comprehensive and differentiated solutions across more markets with a continued focus on affordable, high-quality, culturally-sensitive healthcare services. With the WellCare Acquisition, the Company further broadened its product offerings by adding a Medicare prescription drug plan to its existing business lines. Total consideration paid for the acquisition was $17,605 million, consisting of Centene common shares valued at $11,431 million (based on Centene’s stock price of $66.76), $6,079 million in cash, and $95 million related to the fair value of replacement equity awards associated with pre-combination service. Each WellCare share was converted into 3.38 of validly issued, fully paid, non-assessable shares of Centene common stock and $120.00 in cash. In total, 171 million shares of Centene common stock were issued to the WellCare stockholders. The cash portion of the acquisition was funded through the issuance of long-term debt as further discussed in Note 7. Debt . The Company also recognized $62 million and $446 million of acquisition related costs, primarily related to WellCare, that were in the Consolidated Statements of Operations for the three and nine months ended September 30, 2020, respectively. The acquisition of WellCare was accounted for as a business combination using the acquisition method of accounting that requires assets acquired and liabilities assumed to be recognized at fair value as of the acquisition date. The significant areas of the assessment of fair value that remain preliminary include identifiable intangible assets and goodwill, medical claims liability, and income taxes and, accordingly, the Company has recorded provisional amounts which are subject to adjustment. Measurement period adjustments will be recorded in the period in which they are determined, as if they had been completed at the acquisition date. The Company’s preliminary allocation of the fair value of assets acquired and liabilities assumed as of the acquisition date of January 23, 2020 is as follows ($ in millions): Assets acquired and liabilities assumed Cash and cash equivalents $ 2,947 Premium and related receivables 4,254 Short-term investments 355 Other current assets 1,154 Long-term investments 2,725 Restricted deposits 320 Property, software and equipment 259 Intangible assets (a) 6,552 Other long-term assets 306 Total assets acquired 18,872 Medical claims liability 4,137 Accounts payable and accrued expenses 3,487 Return of premium payable 506 Unearned revenue 402 Long-term debt (b) 2,055 Deferred tax liabilities (c) 1,376 Other long-term liabilities 475 Total liabilities assumed 12,438 Total identifiable net assets 6,434 Goodwill (d) 11,171 Total assets acquired and liabilities assumed $ 17,605 The Company has made the following preliminary fair value adjustments based on information reviewed through September 30, 2020. Significant fair value adjustments are noted as follows: (a) The identifiable intangible assets acquired are to be measured at fair value as of the completion of the acquisition. The fair value of intangible assets will be determined primarily using variations of the income approach, which is based on the present value of the future after tax cash flows attributable to each identified intangible asset. The identifiable intangible assets include purchased contract rights, provider contracts, trade names and developed technologies. Other valuation methods, including the market approach and cost approach, will be considered in estimating the fair value. The Company has estimated the preliminary fair value of intangible assets to be $6,552 million, adjusted from $7,000 million as of June 30, 2020, with a weighted average life of 14 years. The Company adjusted its estimate of the identifiable intangible assets during the third quarter, resulting in an amortization reduction of $34 million. The preliminary fair values and weighted average useful lives for identifiable intangible assets acquired are as follows: Fair Value Weighted Average Useful Life (in years) Purchased contract rights $ 5,650 14 Provider contracts 227 15 Trade names 570 16 Developed technologies 105 3 Total intangible assets acquired $ 6,552 14 (b) Debt is required to be measured at fair value under the acquisition method of accounting. The fair value of WellCare's aggregate principle of $1,950 million Senior Notes assumed in the acquisition was $2,055 million. The $105 million increase will be amortized as a reduction to interest expense over the remaining life of the debt. (c) The preliminary deferred tax liabilities are presented net of $401 million of deferred tax assets. (d) Goodwill is estimated at $11,171 million and primarily relates to synergies expected from the acquisition and the assembled workforce of WellCare. The assignment of goodwill to the Company’s respective segments has not been completed at this time, but the majority of goodwill is expected to be allocated to the Managed Care segment. The majority of the goodwill is not deductible for income tax purposes. Divestitures Immediately prior to the closing of the WellCare Acquisition, Anthem, Inc. acquired WellCare’s Missouri Medicaid health plan, a WellCare Missouri Medicare Advantage health plan, and WellCare’s Nebraska Medicaid health plan. CVS Health Corporation acquired portions of Centene’s Illinois Medicaid and Medicare Advantage health plans as part of previously announced divestiture agreements. The Company recorded $104 million in pre-tax gains for the nine months ended September 30, 2020, as a result of the Illinois divestiture, which is included in investment and other income on the Consolidated Statements of Operations. Unaudited Pro Forma Financial Information The following table presents supplemental pro forma information for the three and nine months ended September 30, 2019 ($ in millions, except per share data): Three Months Ended September 30, 2019 Nine Months Ended September 30, 2019 Total revenues $ 26,074 $ 76,568 Net earnings attributable to common stockholders $ 232 $ 1,370 Diluted earnings per share $ 0.39 $ 2.31 The unaudited pro forma total revenues for the nine months ended September 30, 2020 was $84,617 million. It is impracticable for the Company to determine the pro forma earnings information for the nine months ended September 30, 2020 due to the nature of obtaining that information as the Company immediately began integrating WellCare into its ongoing operations. The unaudited pro forma financial information reflects the historical results of Centene and WellCare adjusted as if the acquisition had occurred on January 1, 2019, primarily for the following: • Interest expense associated with debt incurred to finance the transaction. • Elimination of historical WellCare intangible asset amortization expense and addition of amortization expense based on the preliminary estimated values of identifiable intangible assets of approximately $6,552 million. • Issuance of 171 million shares of Centene common stock in connection with the per share common stock consideration. • Elimination of acquisition related costs. • Adjustments to income tax expense related to pro forma adjustments and increased income tax expense related to IRS Regulation 162(m)(6).

Short-term and Long-term Invest

Short-term and Long-term Investments, Restricted Deposits	9 Months Ended
	Sep. 30, 2020
Investments, Debt and Equity Securities [Abstract]
Short-term and Long-term Investments, Restricted Deposits	Short-term and Long-term Investments, Restricted Deposits Short-term and long-term investments and restricted deposits by investment type consist of the following ($ in millions): September 30, 2020 December 31, 2019 Amortized Gross Gross Fair Amortized Gross Gross Fair Debt securities: U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 1,035 $ 4 $ — $ 1,039 $ 211 $ 1 $ — $ 212 Corporate securities 4,722 236 (20) 4,938 3,629 108 (4) 3,733 Restricted certificates of deposit 104 — — 104 482 — — 482 Restricted cash equivalents 146 — — 146 8 — — 8 Short-term time deposits 33 — — 33 — — — — Municipal securities 2,426 121 (3) 2,544 2,320 69 (1) 2,388 Asset-backed securities 890 13 (5) 898 741 5 (2) 744 Residential mortgage-backed securities 824 29 — 853 464 8 (1) 471 Commercial mortgage-backed securities 567 28 (6) 589 380 9 (1) 388 Equity securities (1) 317 — — 317 — — — — Private equity investments 796 — — 796 664 — — 664 Life insurance contracts 154 — — 154 148 — — 148 Total $ 12,014 $ 431 $ (34) $ 12,411 $ 9,047 $ 200 $ (9) $ 9,238 (1) Investments in equity securities primarily consists of exchange traded funds in fixed income securities. The Company’s investments are debt securities classified as available-for-sale with the exception of equity securities, certain private equity investments and life insurance contracts. The Company’s investment policies are designed to provide liquidity, preserve capital and maximize total return on invested assets with the focus on high credit quality securities. The Company limits the size of investment in any single issuer other than U.S. treasury securities and obligations of U.S. government corporations and agencies. As of September 30, 2020, 97% of the Company’s investments in rated securities carry an investment grade rating by nationally recognized statistical rating organizations. At September 30, 2020, the Company held certificates of deposit, equity securities, private equity investments and life insurance contracts, which did not carry a credit rating. Accrued interest income on available for sale debt securities was $71 million at September 30, 2020, and is included in other current assets on the Consolidated Balance Sheets. The Company’s residential mortgage-backed securities are primarily issued by the Federal National Mortgage Association, Government National Mortgage Association or Federal Home Loan Mortgage Corporation, which carry implicit or explicit guarantees of the U.S. government. The Company’s commercial mortgage-backed securities are primarily senior tranches with a weighted average rating of AA and a weighted average duration of 4 years at September 30, 2020. The fair value of available-for-sale debt securities with gross unrealized losses by investment type and length of time that individual securities have been in a continuous unrealized loss position were as follows ($ in millions): September 30, 2020 December 31, 2019 Less Than 12 Months 12 Months or More Less Than 12 Months 12 Months or More Unrealized Losses Fair Unrealized Losses Fair Unrealized Losses Fair Unrealized Losses Fair Corporate securities $ (18) $ 554 $ (2) $ 26 $ (2) $ 192 $ (2) $ 48 Municipal securities (3) 138 — 1 (1) 185 — 11 Asset-backed securities (3) 198 (2) 107 (1) 153 (1) 151 Residential mortgage-backed securities — 26 — 4 — 44 (1) 81 Commercial mortgage-backed securities (5) 112 (1) 12 (1) 118 — 21 Total $ (29) $ 1,028 $ (5) $ 150 $ (5) $ 692 $ (4) $ 312 As of September 30, 2020, the gross unrealized losses were generated from 1,020 positions out of a total of 5,715 positions. The change in fair value of fixed income securities is primarily a result of movement in interest rates subsequent to the purchase of the security. For each security in an unrealized loss position, the Company assesses whether it intends to sell the security or if it is more likely than not the Company will be required to sell the security before recovery of the amortized cost basis for reasons such as liquidity, contractual or regulatory purposes. If the security meets this criterion, the decline in fair value is recorded in earnings. The Company does not intend to sell these securities prior to maturity and it is not likely that the Company will be required to sell these securities prior to maturity; therefore, the Company did not record an impairment for these securities. In addition, the Company continuously monitors investments for credit losses. Certain investments have experienced a decline in fair value due to changes in credit quality, market interest rates and/or general economic conditions. The Company recognizes an allowance when evidence demonstrates that it is credit related. Evidence of a credit related loss may include rating agency actions, adverse conditions specifically related to the security, or failure of the issuer of the security to make scheduled payments. The contractual maturities of short-term and long-term debt securities and restricted deposits are as follows ($ in millions): September 30, 2020 December 31, 2019 Investments Restricted Deposits Investments Restricted Deposits Amortized Fair Amortized Fair Amortized Fair Amortized Fair One year or less $ 1,332 $ 1,340 $ 760 $ 761 $ 750 $ 752 $ 550 $ 550 One year through five years 3,826 3,989 275 277 3,034 3,106 106 108 Five years through ten years 2,179 2,338 16 17 2,162 2,257 — — Greater than ten years 78 82 — — 48 50 — — Asset-backed securities 2,281 2,340 — — 1,585 1,603 — — Total $ 9,696 $ 10,089 $ 1,051 $ 1,055 $ 7,579 $ 7,768 $ 656 $ 658 Actual maturities may differ from contractual maturities due to call or prepayment options. Equity securities, private equity investments and life insurance contracts are excluded from the table above because they do not have a contractual maturity. The Company has an option to redeem at amortized cost substantially all of the securities included in the greater than ten years category listed above.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Assets and liabilities recorded at fair value in the Consolidated Balance Sheets are categorized based upon observable or unobservable inputs used to estimate fair value. Level inputs are as follows: Level Input: Input Definition: Level I Inputs are unadjusted, quoted prices for identical assets or liabilities in active markets at the measurement date. Level II Inputs other than quoted prices included in Level I that are observable for the asset or liability through corroboration with market data at the measurement date. Level III Unobservable inputs that reflect management’s best estimate of what market participants would use in pricing the asset or liability at the measurement date. The following table summarizes fair value measurements by level at September 30, 2020, for assets and liabilities measured at fair value on a recurring basis ($ in millions): Level I Level II Level III Total Assets Cash and cash equivalents $ 12,198 $ — $ — $ 12,198 Investments: U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 277 $ 5 $ — $ 282 Corporate securities — 4,917 — 4,917 Municipal securities — 2,517 — 2,517 Short-term time deposits — 33 — 33 Asset-backed securities — 898 — 898 Residential mortgage-backed securities — 853 — 853 Commercial mortgage-backed securities — 589 — 589 Equity securities 315 2 — 317 Total investments $ 592 $ 9,814 $ — $ 10,406 Restricted deposits: Cash and cash equivalents $ 146 $ — $ — $ 146 Certificates of deposit — 104 — 104 Corporate securities — 21 — 21 Municipal securities — 27 — 27 U.S. Treasury securities and obligations of U.S. government corporations and agencies 757 — — 757 Total restricted deposits $ 903 $ 152 $ — $ 1,055 Total assets at fair value $ 13,693 $ 9,966 $ — $ 23,659 The following table summarizes fair value measurements by level at December 31, 2019, for assets and liabilities measured at fair value on a recurring basis ($ in millions): Level I Level II Level III Total Assets Cash and cash equivalents $ 12,123 $ — $ — $ 12,123 Investments: U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 73 $ — $ — $ 73 Corporate securities — 3,713 — 3,713 Municipal securities — 2,379 — 2,379 Asset-backed securities — 744 — 744 Residential mortgage-backed securities — 471 — 471 Commercial mortgage-backed securities — 388 — 388 Total investments $ 73 $ 7,695 $ — $ 7,768 Restricted deposits: Cash and cash equivalents $ 8 $ — $ — $ 8 Certificates of deposit — 482 — 482 Corporate securities — 20 — 20 Municipal securities — 9 — 9 U.S. Treasury securities and obligations of U.S. government corporations and agencies 139 — — 139 Total restricted deposits $ 147 $ 511 $ — $ 658 Other long-term assets: Interest rate swap agreements $ — $ 10 $ — $ 10 Total assets at fair value $ 12,343 $ 8,216 $ — $ 20,559 Liabilities Other long-term liabilities: Interest rate swap agreements $ — $ 11 $ — $ 11 Total liabilities at fair value $ — $ 11 $ — $ 11 The Company utilizes matrix-pricing services to estimate fair value for securities which are not actively traded on the measurement date. The Company designates these securities as Level II fair value measurements. In addition, the aggregate carrying amount of the Company’s private equity investments and life insurance contracts, which approximates fair value, was $950 million and $812 million as of September 30, 2020 and December 31, 2019, respectively.

Medical Claims Liability

Medical Claims Liability	9 Months Ended
	Sep. 30, 2020
Insurance [Abstract]
Medical Claims Liability	Medical Claims Liability The following table summarizes the change in medical claims liability ($ in millions): Nine Months Ended September 30, 2020 2019 Balance, January 1 $ 7,473 $ 6,831 Less: Reinsurance recoverable 20 27 Balance, January 1, net 7,453 6,804 Acquisitions and divestitures 3,872 57 Incurred related to: Current year 64,105 44,283 Prior years (446) (641) Total incurred 63,659 43,642 Paid related to: Current year 56,074 36,972 Prior years 6,032 5,577 Total paid 62,106 42,549 Balance at September 30, net 12,878 7,954 Plus: Reinsurance recoverable 21 21 Balance, September 30 $ 12,899 $ 7,975 Reinsurance recoverables related to medical claims are included in premium and trade receivables. Changes in estimates of incurred claims for prior years are primarily attributable to reserving under moderately adverse conditions. Additionally, as a result of minimum health benefits ratio (HBR) and other return of premium programs, the Company recorded $97 million and $64 million as a reduction to premium revenue in the nine months ended September 30, 2020 and 2019, respectively. Incurred but not reported (IBNR) plus expected development on reported claims as of September 30, 2020 was $8,307 million. Total IBNR plus expected development on reported claims represents estimates for claims incurred but not reported, development on reported claims, and estimates for the costs necessary to process unpaid claims at the end of each period. The Company estimates its liability using actuarial methods that are commonly used by health insurance actuaries and meet Actuarial Standards of Practice. These actuarial methods consider factors such as historical data for payment patterns, cost trends, product mix, seasonality, utilization of healthcare services and other relevant factors.

Affordable Care Act

Affordable Care Act	9 Months Ended
	Sep. 30, 2020
Affordable Care Act [Abstract]
Affordable Care Act	Affordable Care Act The Affordable Care Act established risk spreading premium stabilization programs as well as a minimum annual medical loss ratio (MLR) and cost sharing reductions. The Company's net receivables (payables) for each of the programs are as follows ($ in millions): September 30, 2020 December 31, 2019 Risk adjustment receivable $ 400 $ 245 Risk adjustment payable (1,038) (1,239) Risk corridor receivable 457 4 Minimum medical loss ratio (195) (367) Cost sharing reduction receivable 122 73 Cost sharing reduction payable (1) (1) In April 2020, the U.S. Supreme Court ruled that the federal government was required to pay health insurers for payments due under the risk corridor program, originally established under the Affordable Care Act (ACA). In the third quarter of 2020, the Company recorded a pre-tax net benefit related to the ACA risk corridor receivable settlement of $398 million (net of minimum medical loss ratio payback and related expenses). The Company received substantially all of the risk corridor receivable in October 2020. In July 2020, the Centers for Medicare and Medicaid Services (CMS) announced the final risk adjustment transfers for the 2019 benefit year. As a result of the announcement, the Company reduced its risk adjustment net payables by $94 million from December 31, 2019. After consideration of minimum MLR, estimated Risk Adjustment Data Validation (RADV) audit results, and other related impacts, the net pre-tax benefit recognized was $63 million recorded in the second quarter of 2020.

Debt

Debt	9 Months Ended
	Sep. 30, 2020
Debt Disclosure [Abstract]
Debt	Debt Debt consists of the following ($ in millions): September 30, 2020 December 31, 2019 $1,000 million 4.75% Senior Notes, due May 15, 2022 $ 1,005 $ 1,004 $1,000 million 6.125% Senior Notes, due February 15, 2024 — 1,000 $2,200 million 4.75% Senior Notes, due January 15, 2025 2,233 2,228 $1,200 million 5.25% Senior Notes due April 1, 2025 1,245 — $1,800 million 5.375% Senior Notes, due June 1, 2026 1,800 1,800 $750 million 5.375% Senior Notes due August 15, 2026 796 — $2,500 million 4.25% Senior Notes due December 15, 2027 2,481 2,479 $3,500 million 4.625% Senior Notes due December 15, 2029 3,500 3,500 $2,000 million 3.375% Senior Notes due February 15, 2030 2,000 — Fair value of interest rate swap agreements — (1) Total senior notes 15,060 12,010 Term loan credit facility 1,450 1,450 Revolving credit agreement 93 93 Mortgage notes payable 51 54 Construction loan payable 177 140 Finance leases and other 137 122 Debt issuance costs (142) (143) Total debt 16,826 13,726 Less current portion (89) (88) Long-term debt $ 16,737 $ 13,638 Senior Notes In connection with the WellCare Acquisition, in January 2020, the Company completed an exchange offer for up to $1,200 million of 5.25% Senior Notes due April 1, 2025 and $750 million of 5.375% Senior Notes due August 15, 2026 (collectively, the WellCare Notes) issued by WellCare and issued $1,146 million aggregate principal amount of 5.25% Senior Notes due April 1, 2025 and $747 million aggregate principal amount of 5.375% Senior Notes due August 15, 2026. Additionally, the Company’s wholly owned subsidiary, WellCare Health Plans, Inc., assumed the remaining unexchanged WellCare Notes. The WellCare Notes were recorded at the acquisition date fair value of $2,055 million. In February 2020, the Company issued $2,000 million 3.375% Senior Notes due February 15, 2030 (the $2,000 million 2030 Notes). The Company used the net proceeds from the $2,000 million 2030 Notes to redeem all of its outstanding $1,000 million 6.125% Senior Notes, due February 15, 2024 (the 2024 Notes). The Company recognized a pre-tax loss on extinguishment of approximately $44 million, including the call premium, the write-off of unamortized debt issuance costs and the loss on the termination of the $1,000 million interest rate swap associated with the 2024 Notes. The Company also intended to use remaining proceeds to redeem its $1,000 million 4.75% Senior Notes due May 15, 2022 (the 2022 Notes). However, as a result of the spread of COVID-19 and the resulting disruption and volatility in the global capital markets, the Company deferred the redemption of the 2022 Notes. The 2022 Notes were redeemed in the fourth quarter in connection with an additional offering of senior notes as further described below, and the Company decided to increase liquidity with the remaining proceeds of the $2,000 million 2030 Notes. In May 2020, the Company completed an exchange offer, whereby it exchanged substantially all of the outstanding $2,000 million 3.375% Senior Notes due February 15, 2030, $1,000 million 4.75% Senior Notes due January 15, 2025, $2,500 million 4.25% Senior Notes due December 15, 2027, and $3,500 million 4.625% Senior Notes due December 15, 2029 for identical securities that have been registered under the Securities Act of 1933. In October 2020, the Company issued $2,200 million 3.0% Senior Notes due October 2030 (the $2,200 million 2030 Notes). The Company used the net proceeds from the offering, together with cash on hand, to redeem all of the 2022 Notes and the $1,200 million 5.25% Senior Notes due 2025, including all premiums, accrued interest and expenses related to the redemptions. The Company recognized a pre-tax loss on extinguishment of $17 million on the redemption of the 2022 Notes and the $1,200 million 5.25% Senior Notes due 2025 in the fourth quarter of 2020, including the call premium and write-off of unamortized debt issuance costs. Interest Rate Swaps In February 2020, the Company terminated the interest rate swap agreements associated with the 2022 Notes and $2,200 million 4.75% Senior Notes, due January 15, 2025, (the 2025 Notes). The interest rate swaps associated with the 2024 Notes were also terminated in connection with the redemption of those notes as discussed above. In total, the Company terminated three interest rate swap contracts with a notional amount of $2,100 million. The swaps effectively converted $2,100 million of fixed rate notes to floating rates. As a result of the interest rate swap terminations, the Company received $9 million in cash. The corresponding net gain on the 2022 Notes and 2025 Notes is being amortized as a reduction to interest expense over the remaining term of the respective notes.

Leases

Leases	9 Months Ended
	Sep. 30, 2020
Leases [Abstract]
Leases	Leases The Company records right of use (ROU) assets and lease liabilities for non-cancelable operating leases primarily for real estate and equipment. Leases with an initial term of 12 months or less are not recorded on the balance sheet. Expense related to leases is recorded on a straight-line basis over the lease term, including rent holidays. During the three and nine months ended September 30, 2020, the Company recognized operating lease expense of $68 million and $202 million, respectively. The following table sets forth the ROU assets and lease liabilities as of September 30, 2020 ($ in millions): September 30, 2020 Assets ROU assets (recorded within other long-term assets) $ 1,088 Liabilities Short-term (recorded within accounts payable and accrued expenses) $ 198 Long-term (recorded within other long-term liabilities) 1,039 Total lease liabilities $ 1,237 During the three and nine months ended September 30, 2020, the Company reduced its lease liabilities by $67 million and $198 million, respectively, for cash paid. In addition, during the three and nine months ended September 30, 2020, new operating leases commenced resulting in the recognition of ROU assets and lease liabilities of $55 million and $114 million, respectively. As of September 30, 2020, the Company had additional operating leases that have not yet commenced of $52 million, which included one significant lease executed during 2019. This operating lease will commence in 2020 with a lease term of 10 years. In connection with the WellCare acquisition, the Company acquired approximately $300 million of ROU assets and $300 million of lease liabilities. As of September 30, 2020, the weighted average remaining lease term of the Company’s operating leases was 8.5 years. The lease liabilities as of September 30, 2020 reflect a weighted average discount rate of 3.7%. Lease payments over the next five years and thereafter are as follows ($ in millions): September 30, 2020 2020 $ 49 2021 250 2022 210 2023 176 2024 150 2025 115 Thereafter 514 Total lease payments 1,464 Less: imputed interest (227) Total lease liabilities $ 1,237

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2020
Equity [Abstract]
Stockholders' Equity	Stockholders' Equity In January 2020, the Company issued 171 million shares of Centene common stock with a fair value of $11,431 million and paid $6,079 million in cash in exchange for all the outstanding shares of WellCare common stock. In addition, the Company recorded $95 million related to the fair value of replacement equity awards associated with pre-combination service. During the first quarter of 2020, the Company used proceeds from divestitures to repurchase 8,672 thousand shares of Centene common stock for $500 million through the Company’s stock repurchase program. As of September 30, 2020, the Company has a remaining amount of 5,488 thousand shares available under the program. The remaining common stock repurchases during the nine months ended September 30, 2020 relate to the purchase of shares to satisfy tax withholding requirements in connection with employee equity awards.

Earnings Per Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2020
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share The following table sets forth the calculation of basic and diluted net earnings per common share ($ in millions, except per share data in dollars and shares in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2020 2019 2020 2019 Earnings attributable to Centene Corporation $ 568 $ 95 $ 1,820 $ 1,112 Shares used in computing per share amounts: Weighted average number of common shares outstanding 579,510 413,616 567,586 413,302 Common stock equivalents (as determined by applying the treasury stock method) 8,461 6,340 8,146 6,398 Weighted average number of common shares and potential dilutive common shares outstanding 587,971 419,956 575,732 419,700 Net earnings per common share attributable to Centene Corporation: Basic earnings per common share $ 0.98 $ 0.23 $ 3.21 $ 2.69 Diluted earnings per common share $ 0.97 $ 0.23 $ 3.16 $ 2.65 The calculation of diluted earnings per common share for the three and nine months ended September 30, 2020 excludes the impact of 64 thousand and 75 thousand shares, respectively, related to anti-dilutive stock options, restricted stock and restricted stock units. The calculation of diluted earnings per common share for the three and nine months ended September 30, 2019 excludes the impact of 1,532 thousand and 1,424 thousand shares, respectively, related to anti-dilutive stock options, restricted stock and restricted stock units.

Segment Information

Segment Information	9 Months Ended
	Sep. 30, 2020
Segment Reporting [Abstract]
Segment Information	Segment Information Centene operates in two segments: Managed Care and Specialty Services. The Managed Care segment consists of Centene’s health plans, including all of the functions needed to operate them. Subsequent to the closing of the WellCare Acquisition, the Managed Care segment also includes WellCare’s legacy Medicaid Health Plans, Medicare Health Plans and Medicare Prescription Drug Plan (PDP) segments. The Specialty Services segment consists of Centene’s specialty companies offering auxiliary healthcare services and products. Factors used in determining the reportable business segments include the nature of operating activities, the existence of separate senior management teams, and the type of information presented to the Company’s chief operating decision-maker to evaluate all results of operations. Segment information for the three months ended September 30, 2020, follows ($ in millions): Managed Care Specialty Eliminations Consolidated Total revenues from external customers $ 28,014 $ 1,076 $ — $ 29,090 Total revenues from internal customers 104 2,987 (3,091) — Total revenues $ 28,118 $ 4,063 $ (3,091) $ 29,090 Earnings from operations $ 888 $ (27) $ — $ 861 Segment information for the three months ended September 30, 2019, follows ($ in millions): Managed Care Specialty Eliminations Consolidated Total revenues from external customers $ 18,087 $ 889 $ — $ 18,976 Total revenues from internal customers 44 2,675 (2,719) — Total revenues $ 18,131 $ 3,564 $ (2,719) $ 18,976 Earnings from operations $ 385 $ (209) $ — $ 176 Segment information for the nine months ended September 30, 2020, follows ($ in millions): Managed Care Specialty Eliminations Consolidated Total revenues from external customers $ 79,573 $ 3,254 $ — $ 82,827 Total revenues from internal customers 321 8,804 (9,125) — Total revenues $ 79,894 $ 12,058 $ (9,125) $ 82,827 Earnings from operations $ 3,014 $ 53 $ — $ 3,067 Segment information for the nine months ended September 30, 2019, follows ($ in millions): Managed Care Specialty Eliminations Consolidated Total revenues from external customers $ 53,283 $ 2,493 $ — $ 55,776 Total revenues from internal customers 116 7,681 (7,797) — Total revenues $ 53,399 $ 10,174 $ (7,797) $ 55,776 Earnings from operations $ 1,587 $ (83) $ — $ 1,504

Contingencies

Contingencies	9 Months Ended
	Sep. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
Contingencies	Contingencies Overview The Company is routinely subjected to legal and regulatory proceedings in the normal course of business. These matters can include, without limitation: • periodic compliance and other reviews and investigations by various federal and state regulatory agencies with respect to requirements applicable to the Company’s business, including, without limitation, those related to payment of out-of-network claims, submissions to CMS for risk adjustment payments or the False Claims Act, submissions to state agencies related to payments or state false claims acts, pre-authorization penalties, timely review of grievances and appeals, timely and accurate payment of claims, and the Health Insurance Portability and Accountability Act of 1996 and other federal and state fraud, waste and abuse laws; • litigation arising out of general business activities, such as tax matters, disputes related to healthcare benefits coverage or reimbursement, putative securities class actions and medical malpractice, privacy, real estate, intellectual property and employment-related claims; • disputes regarding reinsurance arrangements, claims arising out of the acquisition or divestiture of various assets, class actions and claims relating to the performance of contractual and non-contractual obligations to providers, members, employer groups and others, including, but not limited to, the alleged failure to properly pay claims and challenges to the manner in which the Company processes claims and claims alleging that the Company has engaged in unfair business practices. Among other things, these matters may result in awards of damages, fines or penalties, which could be substantial, and/or could require changes to the Company’s business. The Company intends to vigorously defend itself against legal and regulatory proceedings to which it is currently a party; however, these proceedings are subject to many uncertainties. In some of the cases pending against the Company, substantial non-economic or punitive damages are being sought. The Company records reserves and accrues costs for certain legal proceedings and regulatory matters to the extent that it determines an unfavorable outcome is probable and the amount of the loss can be reasonably estimated. While such reserves and accrued costs reflect the Company’s best estimate of the probable loss for such matters, the recorded amounts may differ materially from the actual amount of any such losses. In some cases, no estimate of the possible loss or range of loss in excess of amounts accrued, if any, can be made because of the inherently unpredictable nature of legal and regulatory proceedings, which may be exacerbated by various factors, including but not limited to, they may involve indeterminate claims for monetary damages or may involve fines, penalties or punitive damages; present novel legal theories or legal uncertainties; involve disputed facts; represent a shift in regulatory policy; involve a large number of parties, claimants or regulatory bodies; are in the early stages of the proceedings; involve a number of separate proceedings and/or a wide range of potential outcomes; or result in a change of business practices. As of the date of this report, amounts accrued for legal proceedings and regulatory matters were not material. However, it is possible that in a particular quarter or annual period the Company’s financial condition, results of operations, cash flow and/or liquidity could be materially adversely affected by an ultimate unfavorable resolution of, or development in, legal and/or regulatory proceedings, including as described below. Except for the proceedings discussed below, the Company believes that the ultimate outcome of any of the regulatory and legal proceedings that are currently pending against it should not have a material adverse effect on financial condition, results of operations, cash flow or liquidity. California On October 20, 2015, the Company’s California subsidiary, Health Net of California, Inc. (Health Net California), was named as a defendant in a California taxpayer action filed in Los Angeles County Superior Court, captioned as Michael D. Myers v. State Board of Equalization, Dave Jones, Insurance Commissioner of the State of California, Betty T. Yee, Controller of the State of California, et al., Los Angeles Superior Court Case No. BS158655. This action is brought under a California statute that permits an individual taxpayer to sue a governmental agency when the taxpayer believes the agency has failed to enforce governing law. Plaintiff contends that Health Net California, a California licensed Health Care Service Plan (HCSP), is an “insurer” for purposes of taxation despite acknowledging it is not an “insurer” under regulatory law. Under California law, “insurers” must pay a gross premiums tax (GPT), calculated as 2.35% on gross premiums. As a licensed HCSP, Health Net California has paid the California Corporate Franchise Tax (CFT), the tax generally paid by California businesses. Plaintiff contends that Health Net California must pay the GPT rather than the CFT. Plaintiff seeks a writ of mandate directing the California taxing agencies to collect the GPT, and seeks an order requiring Health Net California to pay GPT, interest and penalties for a period dating to eight years prior to the October 2015 filing of the complaint. This lawsuit is being coordinated with similar lawsuits filed against other entities (collectively, “Related Actions”). In March 2018, the Court overruled the Company’s demurrer seeking to dismiss the complaint and denied the Company’s motion to strike allegations seeking retroactive relief. In August 2018, the trial court stayed all the Related Actions pending determination of a writ of mandate by the California Court of Appeals in two of the Related Actions. In March 2019, the California Court of Appeals denied the writ of mandate. The defendants in those Related Actions sought review by the California Supreme Court, which declined to review the matter. Upon the return of the matter to the Los Angeles County Superior Court, motions for summary judgment were scheduled. Health Net California’s motion for summary judgment was heard by the Court on March 4, 2020. On March 29, 2020, the Court granted Health Net California’s motion for summary judgment. On September 30, 2020, the plaintiff appealed the Court’s decision. The Company intends to continue its vigorous defense against these claims; however, this matter is subject to many uncertainties, and an adverse outcome in this matter could potentially have a materially adverse impact on the Company’s financial position, results of operations and cash flows. Veterans Administration Matter In October 2017, a Civil Investigative Demand (CID) was issued to Health Net Federal Services, LLC (HNFS) by the United States Department of Justice. The CID seeks documents and interrogatory responses concerning whether HNFS submitted, or caused to be submitted, excessive, duplicative or otherwise improper claims to the U.S. Department of Veterans Affairs (VA) under a contract to provide healthcare coordination services for veterans. The contract began in late 2014 and ended September 30, 2018. In 2016, modifications to the contract were made to allow for possible duplicate billings with a reconciliation period at the end of the contract term. The Company is complying with the CID and believes it has met its contractual obligations. At this point, it is not possible to determine what level of liability, if any, the Company may face as a result of this matter. Ambetter Class Action On January 11, 2018, a putative class action lawsuit was filed by Cynthia Harvey and Steven A. Milman against the Company and certain subsidiaries in the U.S. District Court for the Eastern District of Washington. The complaint alleges that the Company failed to meet federal and state requirements for provider networks and directories with regard to its Ambetter policies, denied coverage and/or refused to pay for covered benefits, and failed to address grievances adequately, causing some members to incur unexpected costs. In March 2018, the Company filed separate motions to dismiss each defendant. In July 2018, the plaintiff, Cynthia Harvey, voluntarily filed a First Amended Complaint that removed Steven A. Milman as a plaintiff, dropped Centene Corporation and Superior Health Plan as defendants, abandoned certain claims, narrowed the putative class to Washington State only, and added Centene Management Company as a defendant. In August 2018, the Company moved to dismiss the First Amended Complaint. In response, the plaintiff voluntarily filed a Second Amended Complaint. In September 2018, the Company filed a motion to dismiss the Second Amended Complaint. On November 21, 2018, the Court granted in part and denied in part the Company’s motion to dismiss. The plaintiff filed a Third Amended Complaint, on November 28, 2018, against Centene Management Company and Coordinated Care Corporation (Defendants), both subsidiaries of the Company. Defendants filed an answer on December 12, 2018. The plaintiff filed a motion for class certification on January 8, 2020. The Company opposed and the Court denied the class certification. The plaintiff appealed the class certification denial to the 9th Circuit, but the 9th Circuit dismissed the plaintiff’s appeal on procedural grounds. The case proceeded as an individual lawsuit between a single member and Coordinated Care Corporation until September 15, 2020, when the case was dismissed with prejudice.

Organization and Operations (Po

Organization and Operations (Policies)	9 Months Ended
	Sep. 30, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The accompanying interim financial statements have been prepared under the presumption that users of the interim financial information have either read or have access to the audited financial statements included in the Form 10-K for the fiscal year ended December 31, 2019. The unaudited interim financial statements herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission. Accordingly, footnote disclosures that would substantially duplicate the disclosures contained in the December 31, 2019 audited financial statements have been omitted from these interim financial statements, where appropriate. In the opinion of management, these financial statements reflect all adjustments, consisting only of normal recurring adjustments, which are necessary for a fair presentation of the results of the interim periods presented. Certain 2019 amounts in the consolidated financial statements and notes to the consolidated financial statements have been reclassified to conform to the 2020 presentation. These reclassifications have no effect on net earnings or stockholders’ equity as previously reported. On January 23, 2020, the Company acquired all of the issued and outstanding shares of WellCare Health Plans, Inc. (WellCare) (the WellCare Acquisition). The acquisition was accounted for as a business combination. See Note 2. Acquisitions
Recently Adopted Accounting Guidance and Accounting Guidance Not Yet Adopted	Recently Adopted Accounting Guidance In June 2016, the Financial Accounting Standards Board (FASB) issued an Accounting Standards Update (ASU) which changes how entities measure credit losses for most financial assets and certain other investments that are not measured at fair value through net income. The ASU is intended to improve financial reporting by requiring timelier recording of credit losses on loans and other financial instruments held by financial institutions and other organizations. The amended guidance requires the measurement of all expected credit losses for financial assets (or groups of financial assets) and available for sale debt securities held at the reporting date over the remaining life based on historical experience, current conditions, and reasonable and supportable forecasts. The guidance is effective for annual and interim periods beginning after December 15, 2019. The Company adopted the new guidance in the first quarter of 2020. The majority of the Company’s receivables and other financial instruments are with government entities and, therefore, the adoption did not have a material impact on its receivables and other financial instruments. The Company evaluated its investment portfolio under the new available-for-sale debt securities impairment model guidance. The vast majority of the Company’s investment portfolio are low risk, investment grade securities. The impact of the Company’s evaluation of the investment portfolio resulted in an immaterial decrease to retained earnings at January 1, 2020. The Company evaluates available-for-sale debt securities on a regular basis and records an allowance for credit losses, if necessary. The comparative information has not been restated and continues to be reported under the accounting standards in effect for those periods. The new guidance did not have a material impact on the Company’s consolidated financial position, results of operations or cash flows. In August 2018, the FASB issued an ASU which aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal use software license). The accounting for the service element of a hosting arrangement that is a service contract is not affected by the amendments in this update. The amendments in this ASU require an entity that is the customer in a hosting arrangement to follow the guidance on internal-use software to determine which implementation costs to capitalize and which costs to expense. The standard also requires an entity that is the customer to expense the capitalized implementation costs of a hosting arrangement over the term of the hosting arrangement. The new guidance requires an entity to present the expense related to the capitalized implementation costs in the same line item in the statement of income as the fees associated with the hosting element of the arrangement and classify payments for capitalized implementation costs in the statement of cash flows in the same manner as payments made for fees associated with the hosting element. The entity is also required to present the capitalized implementation costs in the statement of financial position in the same line item that a prepayment for the fees of the associated hosting arrangement would be presented. The guidance is effective for annual and interim periods beginning after December 15, 2019. The Company adopted the new guidance in the first quarter of 2020. The new guidance did not have a material impact on the Company’s consolidated financial position, results of operations or cash flows. Recent Accounting Guidance Not Yet Adopted In December 2019, the FASB issued an ASU which simplifies the accounting for income taxes by removing certain exceptions to the general principles in ASC Topic 740. The ASU also clarifies and amends certain areas of ASC Topic 740 to improve consistent application of and simplify the generally accepted accounting principles within Topic 740. The guidance is effective for annual and interim periods beginning after December 15, 2020. The Company is continuing to evaluate the potential impact of the ASU on the Company’s consolidated financial position, results of operations and cash flows but expects the impact to be immaterial.

Acquisitions (Tables)

Acquisitions (Tables)	9 Months Ended
	Sep. 30, 2020
Business Combinations [Abstract]
Schedule of Allocation of the Fair Value of Assets Acquired and Liabilities Assumed	The Company’s preliminary allocation of the fair value of assets acquired and liabilities assumed as of the acquisition date of January 23, 2020 is as follows ($ in millions): Assets acquired and liabilities assumed Cash and cash equivalents $ 2,947 Premium and related receivables 4,254 Short-term investments 355 Other current assets 1,154 Long-term investments 2,725 Restricted deposits 320 Property, software and equipment 259 Intangible assets (a) 6,552 Other long-term assets 306 Total assets acquired 18,872 Medical claims liability 4,137 Accounts payable and accrued expenses 3,487 Return of premium payable 506 Unearned revenue 402 Long-term debt (b) 2,055 Deferred tax liabilities (c) 1,376 Other long-term liabilities 475 Total liabilities assumed 12,438 Total identifiable net assets 6,434 Goodwill (d) 11,171 Total assets acquired and liabilities assumed $ 17,605
Schedule of Fair Values and Weighted Average Useful Lives for Intangible Assets Acquired	The preliminary fair values and weighted average useful lives for identifiable intangible assets acquired are as follows: Fair Value Weighted Average Useful Life (in years) Purchased contract rights $ 5,650 14 Provider contracts 227 15 Trade names 570 16 Developed technologies 105 3 Total intangible assets acquired $ 6,552 14
Supplement Pro Forma Information	The following table presents supplemental pro forma information for the three and nine months ended September 30, 2019 ($ in millions, except per share data): Three Months Ended September 30, 2019 Nine Months Ended September 30, 2019 Total revenues $ 26,074 $ 76,568 Net earnings attributable to common stockholders $ 232 $ 1,370 Diluted earnings per share $ 0.39 $ 2.31

Short-term and Long-term Inve_2

Short-term and Long-term Investments, Restricted Deposits (Tables)	9 Months Ended
	Sep. 30, 2020
Investments, Debt and Equity Securities [Abstract]
Short-term and long-term investments and restricted deposits by investment type	Short-term and long-term investments and restricted deposits by investment type consist of the following ($ in millions): September 30, 2020 December 31, 2019 Amortized Gross Gross Fair Amortized Gross Gross Fair Debt securities: U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 1,035 $ 4 $ — $ 1,039 $ 211 $ 1 $ — $ 212 Corporate securities 4,722 236 (20) 4,938 3,629 108 (4) 3,733 Restricted certificates of deposit 104 — — 104 482 — — 482 Restricted cash equivalents 146 — — 146 8 — — 8 Short-term time deposits 33 — — 33 — — — — Municipal securities 2,426 121 (3) 2,544 2,320 69 (1) 2,388 Asset-backed securities 890 13 (5) 898 741 5 (2) 744 Residential mortgage-backed securities 824 29 — 853 464 8 (1) 471 Commercial mortgage-backed securities 567 28 (6) 589 380 9 (1) 388 Equity securities (1) 317 — — 317 — — — — Private equity investments 796 — — 796 664 — — 664 Life insurance contracts 154 — — 154 148 — — 148 Total $ 12,014 $ 431 $ (34) $ 12,411 $ 9,047 $ 200 $ (9) $ 9,238 (1) Investments in equity securities primarily consists of exchange traded funds in fixed income securities.
Fair value of available-for-sale investments with gross unrealized losses by investment type and length of time	The fair value of available-for-sale debt securities with gross unrealized losses by investment type and length of time that individual securities have been in a continuous unrealized loss position were as follows ($ in millions): September 30, 2020 December 31, 2019 Less Than 12 Months 12 Months or More Less Than 12 Months 12 Months or More Unrealized Losses Fair Unrealized Losses Fair Unrealized Losses Fair Unrealized Losses Fair Corporate securities $ (18) $ 554 $ (2) $ 26 $ (2) $ 192 $ (2) $ 48 Municipal securities (3) 138 — 1 (1) 185 — 11 Asset-backed securities (3) 198 (2) 107 (1) 153 (1) 151 Residential mortgage-backed securities — 26 — 4 — 44 (1) 81 Commercial mortgage-backed securities (5) 112 (1) 12 (1) 118 — 21 Total $ (29) $ 1,028 $ (5) $ 150 $ (5) $ 692 $ (4) $ 312
Contractual maturities of short-term and long-term investments and restricted deposits	The contractual maturities of short-term and long-term debt securities and restricted deposits are as follows ($ in millions): September 30, 2020 December 31, 2019 Investments Restricted Deposits Investments Restricted Deposits Amortized Fair Amortized Fair Amortized Fair Amortized Fair One year or less $ 1,332 $ 1,340 $ 760 $ 761 $ 750 $ 752 $ 550 $ 550 One year through five years 3,826 3,989 275 277 3,034 3,106 106 108 Five years through ten years 2,179 2,338 16 17 2,162 2,257 — — Greater than ten years 78 82 — — 48 50 — — Asset-backed securities 2,281 2,340 — — 1,585 1,603 — — Total $ 9,696 $ 10,089 $ 1,051 $ 1,055 $ 7,579 $ 7,768 $ 656 $ 658

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2020
Fair Value Disclosures [Abstract]
Assets and Liabilities, Based Upon Observable or Unobservable Inputs, Level Input Definitions	Assets and liabilities recorded at fair value in the Consolidated Balance Sheets are categorized based upon observable or unobservable inputs used to estimate fair value. Level inputs are as follows: Level Input: Input Definition: Level I Inputs are unadjusted, quoted prices for identical assets or liabilities in active markets at the measurement date. Level II Inputs other than quoted prices included in Level I that are observable for the asset or liability through corroboration with market data at the measurement date. Level III Unobservable inputs that reflect management’s best estimate of what market participants would use in pricing the asset or liability at the measurement date.
Fair Value Measurements by Level for Assets and Liabilities Measured at Fair Value on a Recurring Basis	The following table summarizes fair value measurements by level at September 30, 2020, for assets and liabilities measured at fair value on a recurring basis ($ in millions): Level I Level II Level III Total Assets Cash and cash equivalents $ 12,198 $ — $ — $ 12,198 Investments: U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 277 $ 5 $ — $ 282 Corporate securities — 4,917 — 4,917 Municipal securities — 2,517 — 2,517 Short-term time deposits — 33 — 33 Asset-backed securities — 898 — 898 Residential mortgage-backed securities — 853 — 853 Commercial mortgage-backed securities — 589 — 589 Equity securities 315 2 — 317 Total investments $ 592 $ 9,814 $ — $ 10,406 Restricted deposits: Cash and cash equivalents $ 146 $ — $ — $ 146 Certificates of deposit — 104 — 104 Corporate securities — 21 — 21 Municipal securities — 27 — 27 U.S. Treasury securities and obligations of U.S. government corporations and agencies 757 — — 757 Total restricted deposits $ 903 $ 152 $ — $ 1,055 Total assets at fair value $ 13,693 $ 9,966 $ — $ 23,659 The following table summarizes fair value measurements by level at December 31, 2019, for assets and liabilities measured at fair value on a recurring basis ($ in millions): Level I Level II Level III Total Assets Cash and cash equivalents $ 12,123 $ — $ — $ 12,123 Investments: U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 73 $ — $ — $ 73 Corporate securities — 3,713 — 3,713 Municipal securities — 2,379 — 2,379 Asset-backed securities — 744 — 744 Residential mortgage-backed securities — 471 — 471 Commercial mortgage-backed securities — 388 — 388 Total investments $ 73 $ 7,695 $ — $ 7,768 Restricted deposits: Cash and cash equivalents $ 8 $ — $ — $ 8 Certificates of deposit — 482 — 482 Corporate securities — 20 — 20 Municipal securities — 9 — 9 U.S. Treasury securities and obligations of U.S. government corporations and agencies 139 — — 139 Total restricted deposits $ 147 $ 511 $ — $ 658 Other long-term assets: Interest rate swap agreements $ — $ 10 $ — $ 10 Total assets at fair value $ 12,343 $ 8,216 $ — $ 20,559 Liabilities Other long-term liabilities: Interest rate swap agreements $ — $ 11 $ — $ 11 Total liabilities at fair value $ — $ 11 $ — $ 11

Medical Claims Liability (Table

Medical Claims Liability (Tables)	9 Months Ended
	Sep. 30, 2020
Insurance [Abstract]
Schedule of change in medical claims liability	The following table summarizes the change in medical claims liability ($ in millions): Nine Months Ended September 30, 2020 2019 Balance, January 1 $ 7,473 $ 6,831 Less: Reinsurance recoverable 20 27 Balance, January 1, net 7,453 6,804 Acquisitions and divestitures 3,872 57 Incurred related to: Current year 64,105 44,283 Prior years (446) (641) Total incurred 63,659 43,642 Paid related to: Current year 56,074 36,972 Prior years 6,032 5,577 Total paid 62,106 42,549 Balance at September 30, net 12,878 7,954 Plus: Reinsurance recoverable 21 21 Balance, September 30 $ 12,899 $ 7,975

Affordable Care Act (Tables)

Affordable Care Act (Tables)	9 Months Ended
	Sep. 30, 2020
Affordable Care Act [Abstract]
Schedule of net receivables (payables) related to the Affordable Care Act Programs	The Company's net receivables (payables) for each of the programs are as follows ($ in millions): September 30, 2020 December 31, 2019 Risk adjustment receivable $ 400 $ 245 Risk adjustment payable (1,038) (1,239) Risk corridor receivable 457 4 Minimum medical loss ratio (195) (367) Cost sharing reduction receivable 122 73 Cost sharing reduction payable (1) (1)

Debt (Tables)

Debt (Tables)	9 Months Ended
	Sep. 30, 2020
Debt Disclosure [Abstract]
Schedule of Debt	Debt consists of the following ($ in millions): September 30, 2020 December 31, 2019 $1,000 million 4.75% Senior Notes, due May 15, 2022 $ 1,005 $ 1,004 $1,000 million 6.125% Senior Notes, due February 15, 2024 — 1,000 $2,200 million 4.75% Senior Notes, due January 15, 2025 2,233 2,228 $1,200 million 5.25% Senior Notes due April 1, 2025 1,245 — $1,800 million 5.375% Senior Notes, due June 1, 2026 1,800 1,800 $750 million 5.375% Senior Notes due August 15, 2026 796 — $2,500 million 4.25% Senior Notes due December 15, 2027 2,481 2,479 $3,500 million 4.625% Senior Notes due December 15, 2029 3,500 3,500 $2,000 million 3.375% Senior Notes due February 15, 2030 2,000 — Fair value of interest rate swap agreements — (1) Total senior notes 15,060 12,010 Term loan credit facility 1,450 1,450 Revolving credit agreement 93 93 Mortgage notes payable 51 54 Construction loan payable 177 140 Finance leases and other 137 122 Debt issuance costs (142) (143) Total debt 16,826 13,726 Less current portion (89) (88) Long-term debt $ 16,737 $ 13,638

Leases (Tables)

Leases (Tables)	9 Months Ended
	Sep. 30, 2020
Leases [Abstract]
ROU Assets and Liabilities	The following table sets forth the ROU assets and lease liabilities as of September 30, 2020 ($ in millions): September 30, 2020 Assets ROU assets (recorded within other long-term assets) $ 1,088 Liabilities Short-term (recorded within accounts payable and accrued expenses) $ 198 Long-term (recorded within other long-term liabilities) 1,039 Total lease liabilities $ 1,237
Maturity of Operating Lease Liabilities	Lease payments over the next five years and thereafter are as follows ($ in millions): September 30, 2020 2020 $ 49 2021 250 2022 210 2023 176 2024 150 2025 115 Thereafter 514 Total lease payments 1,464 Less: imputed interest (227) Total lease liabilities $ 1,237

Earnings Per Share (Tables)

Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2020
Earnings Per Share [Abstract]
Calculation of Basic and Diluted Net Earnings Per Common Share	The following table sets forth the calculation of basic and diluted net earnings per common share ($ in millions, except per share data in dollars and shares in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2020 2019 2020 2019 Earnings attributable to Centene Corporation $ 568 $ 95 $ 1,820 $ 1,112 Shares used in computing per share amounts: Weighted average number of common shares outstanding 579,510 413,616 567,586 413,302 Common stock equivalents (as determined by applying the treasury stock method) 8,461 6,340 8,146 6,398 Weighted average number of common shares and potential dilutive common shares outstanding 587,971 419,956 575,732 419,700 Net earnings per common share attributable to Centene Corporation: Basic earnings per common share $ 0.98 $ 0.23 $ 3.21 $ 2.69 Diluted earnings per common share $ 0.97 $ 0.23 $ 3.16 $ 2.65

Segment Information (Tables)

Segment Information (Tables)	9 Months Ended
	Sep. 30, 2020
Segment Reporting [Abstract]
Segment Information	Segment information for the three months ended September 30, 2020, follows ($ in millions): Managed Care Specialty Eliminations Consolidated Total revenues from external customers $ 28,014 $ 1,076 $ — $ 29,090 Total revenues from internal customers 104 2,987 (3,091) — Total revenues $ 28,118 $ 4,063 $ (3,091) $ 29,090 Earnings from operations $ 888 $ (27) $ — $ 861 Segment information for the three months ended September 30, 2019, follows ($ in millions): Managed Care Specialty Eliminations Consolidated Total revenues from external customers $ 18,087 $ 889 $ — $ 18,976 Total revenues from internal customers 44 2,675 (2,719) — Total revenues $ 18,131 $ 3,564 $ (2,719) $ 18,976 Earnings from operations $ 385 $ (209) $ — $ 176 Segment information for the nine months ended September 30, 2020, follows ($ in millions): Managed Care Specialty Eliminations Consolidated Total revenues from external customers $ 79,573 $ 3,254 $ — $ 82,827 Total revenues from internal customers 321 8,804 (9,125) — Total revenues $ 79,894 $ 12,058 $ (9,125) $ 82,827 Earnings from operations $ 3,014 $ 53 $ — $ 3,067 Segment information for the nine months ended September 30, 2019, follows ($ in millions): Managed Care Specialty Eliminations Consolidated Total revenues from external customers $ 53,283 $ 2,493 $ — $ 55,776 Total revenues from internal customers 116 7,681 (7,797) — Total revenues $ 53,399 $ 10,174 $ (7,797) $ 55,776 Earnings from operations $ 1,587 $ (83) $ — $ 1,504

Acquisitions - Narrative (Detai

Acquisitions - Narrative (Details) $ / shares in Units, shares in Millions, $ in Millions	Jan. 23, 2020USD ($)$ / sharesshares	Jan. 31, 2020USD ($)shares	Sep. 30, 2020USD ($)	Sep. 30, 2019USD ($)	Sep. 30, 2020USD ($)	Sep. 30, 2019USD ($)	Jun. 30, 2020USD ($)
Business Acquisition [Line Items]
Centene stock price (in usd per share) | $ / shares	$ 66.76
Acquisition related costs			$ 62		$ 446
Gain on divestiture					104	$ 0
Centene Illinois Medicaid and Medicare Advantage Health Plans
Business Acquisition [Line Items]
Gain on divestiture					104
WellCare Health Plans, Inc.
Business Acquisition [Line Items]
Transaction value	$ 19,555
Consideration transferred	17,605
Consideration transferred, shares valued	11,431	$ 11,431
Cash paid	6,079
Consideration transferred related to fair value of replacement equity awards associated with pre-combination service	$ 95
Common stock cancelled and converted into right to Centene common stock	3.38
Cash paid per acquiree share, without interest (in usd per share) | $ / shares	$ 120
Shares issued (in shares) | shares	171	171
Pro forma revenue (unaudited)				$ 26,074	$ 84,617	$ 76,568
Intangible assets	$ 6,552						$ 7,000

Acquisitions - Schedule of Fair

Acquisitions - Schedule of Fair Value of Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Millions	Jan. 23, 2020	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Assets acquired and liabilities assumed
Goodwill		$ 17,964		$ 6,863
WellCare Health Plans, Inc.
Assets acquired and liabilities assumed
Cash and cash equivalents	$ 2,947
Premium and related receivables	4,254
Short-term investments	355
Other current assets	1,154
Long-term investments	2,725
Restricted deposits	320
Property, software and equipment	259
Intangible assets	6,552		$ 7,000
Other long-term assets	306
Total assets acquired	18,872
Medical claims liability	4,137
Accounts payable and accrued expenses	3,487
Return of premium payable	506
Unearned revenue	402
Long-term debt	2,055
Deferred tax liabilities	1,376
Other long-term liabilities	475
Total liabilities assumed	12,438
Total identifiable net assets	6,434
Goodwill	11,171
Total assets acquired and liabilities assumed	$ 17,605
Acquired intangibles, weighted average useful life years	14 years
Debt assumed, aggregate principle	$ 1,950
Debt assumed, excess of principle	105
Deferred tax assets	401
Intangible assets amortization reduction		$ 34
WellCare Health Plans, Inc. | Purchased contract rights
Assets acquired and liabilities assumed
Intangible assets	$ 5,650
Acquired intangibles, weighted average useful life years	14 years
WellCare Health Plans, Inc. | Provider contracts
Assets acquired and liabilities assumed
Intangible assets	$ 227
Acquired intangibles, weighted average useful life years	15 years
WellCare Health Plans, Inc. | Trade names
Assets acquired and liabilities assumed
Intangible assets	$ 570
Acquired intangibles, weighted average useful life years	16 years
WellCare Health Plans, Inc. | Developed technologies
Assets acquired and liabilities assumed
Intangible assets	$ 105
Acquired intangibles, weighted average useful life years	3 years

Acquisitions - Supplemental Pro

Acquisitions - Supplemental Proforma Information (Details) - WellCare Health Plans, Inc. - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Business Acquisition [Line Items]
Total revenues	$ 26,074	$ 84,617	$ 76,568
Net earnings attributable to common stockholders	$ 232		$ 1,370
Diluted earnings per share (in usd per share)	$ 0.39		$ 2.31

Short-term and Long-term Inve_3

Short-term and Long-term Investments, Restricted Deposits - By Investment Type (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Debt Securities
Gross Unrealized Gains	$ 431	$ 200
Gross Unrealized Losses	(34)	(9)
Equity securities	317	0
Private equity investments	796	664
Life insurance contracts	154	148
Total, Amortized Cost	12,014	9,047
Total, Fair Value	12,411	9,238
U.S. Treasury securities and obligations of U.S. government corporations and agencies
Debt Securities
Amortized Cost	1,035	211
Gross Unrealized Gains	4	1
Gross Unrealized Losses	0	0
Fair Value	1,039	212
Corporate securities
Debt Securities
Amortized Cost	4,722	3,629
Gross Unrealized Gains	236	108
Gross Unrealized Losses	(20)	(4)
Fair Value	4,938	3,733
Restricted certificates of deposit
Debt Securities
Amortized Cost	104	482
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	104	482
Restricted cash equivalents
Debt Securities
Amortized Cost	146	8
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	146	8
Short-term time deposits
Debt Securities
Amortized Cost	33	0
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	33	0
Municipal securities
Debt Securities
Amortized Cost	2,426	2,320
Gross Unrealized Gains	121	69
Gross Unrealized Losses	(3)	(1)
Fair Value	2,544	2,388
Asset-backed securities
Debt Securities
Amortized Cost	890	741
Gross Unrealized Gains	13	5
Gross Unrealized Losses	(5)	(2)
Fair Value	898	744
Residential mortgage-backed securities
Debt Securities
Amortized Cost	824	464
Gross Unrealized Gains	29	8
Gross Unrealized Losses	0	(1)
Fair Value	853	471
Commercial mortgage-backed securities
Debt Securities
Amortized Cost	567	380
Gross Unrealized Gains	28	9
Gross Unrealized Losses	(6)	(1)
Fair Value	$ 589	$ 388

Short-term and Long-term Inve_4

Short-term and Long-term Investments, Restricted Deposits - Narrative (Details) $ in Millions	9 Months Ended
	Sep. 30, 2020USD ($)position
Schedule Of Investments And Restricted Deposits By Type [Line Items]
Accrued interest income | $	$ 71
Positions from which gross unrealized losses were generated	1,020
Total unrealized investment positions	5,715
Commercial mortgage-backed securities
Schedule Of Investments And Restricted Deposits By Type [Line Items]
Investments recorded at fair value that carry rating of AA Plus, weighted average (in years)	4 years
Rated Securities | External Credit Rating, Investment Grade
Schedule Of Investments And Restricted Deposits By Type [Line Items]
Percentage of investments in rated securities carry an investment grade rating by nationally recognized statistical rating organizations	97.00%

Short-term and Long-term Inve_5

Short-term and Long-term Investments, Restricted Deposits - Fair Value of Available-For-Sale Investments with Gross Unrealized Losses by Investment Type and Length of Time (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Unrealized Losses
Less Than 12 Months	$ (29)	$ (5)
12 Months or More	(5)	(4)
Fair Value
Fair Value, Less Than 12 Months	1,028	692
Fair Value, 12 Months or More	150	312
Corporate securities
Unrealized Losses
Less Than 12 Months	(18)	(2)
12 Months or More	(2)	(2)
Fair Value
Fair Value, Less Than 12 Months	554	192
Fair Value, 12 Months or More	26	48
Municipal securities
Unrealized Losses
Less Than 12 Months	(3)	(1)
12 Months or More	0	0
Fair Value
Fair Value, Less Than 12 Months	138	185
Fair Value, 12 Months or More	1	11
Asset-backed securities
Unrealized Losses
Less Than 12 Months	(3)	(1)
12 Months or More	(2)	(1)
Fair Value
Fair Value, Less Than 12 Months	198	153
Fair Value, 12 Months or More	107	151
Residential mortgage-backed securities
Unrealized Losses
Less Than 12 Months	0	0
12 Months or More	0	(1)
Fair Value
Fair Value, Less Than 12 Months	26	44
Fair Value, 12 Months or More	4	81
Commercial mortgage-backed securities
Unrealized Losses
Less Than 12 Months	(5)	(1)
12 Months or More	(1)	0
Fair Value
Fair Value, Less Than 12 Months	112	118
Fair Value, 12 Months or More	$ 12	$ 21

Short-term and Long-term Inve_6

Short-term and Long-term Investments, Restricted Deposits - Contractual Maturities of Short-Term and Long-Term Investments and Restricted Deposits (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Investments
Amortized Cost
One year or less	$ 1,332	$ 750
One year through five years	3,826	3,034
Five years through ten years	2,179	2,162
Greater than ten years	78	48
Asset-backed securities	2,281	1,585
Amortized Cost	9,696	7,579
Fair Value
One year or less	1,340	752
One year through five years	3,989	3,106
Five years through ten years	2,338	2,257
Greater than ten years	82	50
Asset-backed securities	2,340	1,603
Fair Value	10,089	7,768
Restricted Deposits
Amortized Cost
One year or less	760	550
One year through five years	275	106
Five years through ten years	16	0
Greater than ten years	0	0
Asset-backed securities	0	0
Amortized Cost	1,051	656
Fair Value
One year or less	761	550
One year through five years	277	108
Five years through ten years	17	0
Greater than ten years	0	0
Asset-backed securities	0	0
Fair Value	$ 1,055	$ 658

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value Measurements by Level for Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Assets
Cash and cash equivalents	$ 12,198	$ 12,123
Investments:
Equity securities	317	0
Other long-term assets:
Total assets at fair value	23,659	20,559
Other long-term liabilities:
Total liabilities at fair value		11
U.S. Treasury securities and obligations of U.S. government corporations and agencies
Investments:
Assets measured at fair value	1,039	212
Corporate securities
Investments:
Assets measured at fair value	4,938	3,733
Municipal securities
Investments:
Assets measured at fair value	2,544	2,388
Short-term time deposits
Investments:
Assets measured at fair value	33	0
Asset-backed securities
Investments:
Assets measured at fair value	898	744
Residential mortgage-backed securities
Investments:
Assets measured at fair value	853	471
Commercial mortgage-backed securities
Investments:
Assets measured at fair value	589	388
Interest rate swap agreements
Other long-term liabilities:
Interest rate swap agreements		11
Available-for-sale
Investments:
Assets measured at fair value	10,406	7,768
Available-for-sale | U.S. Treasury securities and obligations of U.S. government corporations and agencies
Investments:
Assets measured at fair value	282	73
Available-for-sale | Corporate securities
Investments:
Assets measured at fair value	4,917	3,713
Available-for-sale | Municipal securities
Investments:
Assets measured at fair value	2,517	2,379
Available-for-sale | Short-term time deposits
Investments:
Assets measured at fair value	33
Available-for-sale | Asset-backed securities
Investments:
Assets measured at fair value	898	744
Available-for-sale | Residential mortgage-backed securities
Investments:
Assets measured at fair value	853	471
Available-for-sale | Commercial mortgage-backed securities
Investments:
Assets measured at fair value	589	388
Restricted Deposits
Investments:
Assets measured at fair value	1,055	658
Restricted Deposits | U.S. Treasury securities and obligations of U.S. government corporations and agencies
Investments:
Assets measured at fair value	757	139
Restricted Deposits | Corporate securities
Investments:
Assets measured at fair value	21	20
Restricted Deposits | Municipal securities
Investments:
Assets measured at fair value	27	9
Restricted Deposits | Cash and cash equivalents
Investments:
Assets measured at fair value	146	8
Restricted Deposits | Certificates of deposit
Investments:
Assets measured at fair value	104	482
Other long-term assets: | Interest rate swap agreements
Other long-term assets:
Derivative asset		10
Level I
Assets
Cash and cash equivalents	12,198	12,123
Investments:
Equity securities	315
Other long-term assets:
Total assets at fair value	13,693	12,343
Other long-term liabilities:
Total liabilities at fair value		0
Level I | Interest rate swap agreements
Other long-term liabilities:
Interest rate swap agreements		0
Level I | Available-for-sale
Investments:
Assets measured at fair value	592	73
Level I | Available-for-sale | U.S. Treasury securities and obligations of U.S. government corporations and agencies
Investments:
Assets measured at fair value	277	73
Level I | Available-for-sale | Corporate securities
Investments:
Assets measured at fair value	0	0
Level I | Available-for-sale | Municipal securities
Investments:
Assets measured at fair value	0	0
Level I | Available-for-sale | Short-term time deposits
Investments:
Assets measured at fair value	0
Level I | Available-for-sale | Asset-backed securities
Investments:
Assets measured at fair value	0	0
Level I | Available-for-sale | Residential mortgage-backed securities
Investments:
Assets measured at fair value	0	0
Level I | Available-for-sale | Commercial mortgage-backed securities
Investments:
Assets measured at fair value	0	0
Level I | Restricted Deposits
Investments:
Assets measured at fair value	903	147
Level I | Restricted Deposits | U.S. Treasury securities and obligations of U.S. government corporations and agencies
Investments:
Assets measured at fair value	757	139
Level I | Restricted Deposits | Corporate securities
Investments:
Assets measured at fair value	0	0
Level I | Restricted Deposits | Municipal securities
Investments:
Assets measured at fair value	0	0
Level I | Restricted Deposits | Cash and cash equivalents
Investments:
Assets measured at fair value	146	8
Level I | Restricted Deposits | Certificates of deposit
Investments:
Assets measured at fair value	0	0
Level I | Other long-term assets: | Interest rate swap agreements
Other long-term assets:
Derivative asset		0
Level II
Assets
Cash and cash equivalents	0	0
Investments:
Equity securities	2
Other long-term assets:
Total assets at fair value	9,966	8,216
Other long-term liabilities:
Total liabilities at fair value		11
Level II | Interest rate swap agreements
Other long-term liabilities:
Interest rate swap agreements		11
Level II | Available-for-sale
Investments:
Assets measured at fair value	9,814	7,695
Level II | Available-for-sale | U.S. Treasury securities and obligations of U.S. government corporations and agencies
Investments:
Assets measured at fair value	5	0
Level II | Available-for-sale | Corporate securities
Investments:
Assets measured at fair value	4,917	3,713
Level II | Available-for-sale | Municipal securities
Investments:
Assets measured at fair value	2,517	2,379
Level II | Available-for-sale | Short-term time deposits
Investments:
Assets measured at fair value	33
Level II | Available-for-sale | Asset-backed securities
Investments:
Assets measured at fair value	898	744
Level II | Available-for-sale | Residential mortgage-backed securities
Investments:
Assets measured at fair value	853	471
Level II | Available-for-sale | Commercial mortgage-backed securities
Investments:
Assets measured at fair value	589	388
Level II | Restricted Deposits
Investments:
Assets measured at fair value	152	511
Level II | Restricted Deposits | U.S. Treasury securities and obligations of U.S. government corporations and agencies
Investments:
Assets measured at fair value	0	0
Level II | Restricted Deposits | Corporate securities
Investments:
Assets measured at fair value	21	20
Level II | Restricted Deposits | Municipal securities
Investments:
Assets measured at fair value	27	9
Level II | Restricted Deposits | Cash and cash equivalents
Investments:
Assets measured at fair value	0	0
Level II | Restricted Deposits | Certificates of deposit
Investments:
Assets measured at fair value	104	482
Level II | Other long-term assets: | Interest rate swap agreements
Other long-term assets:
Derivative asset		10
Level III
Assets
Cash and cash equivalents	0	0
Investments:
Equity securities	0
Other long-term assets:
Total assets at fair value	0	0
Other long-term liabilities:
Total liabilities at fair value		0
Level III | Interest rate swap agreements
Other long-term liabilities:
Interest rate swap agreements		0
Level III | Available-for-sale
Investments:
Assets measured at fair value	0	0
Level III | Available-for-sale | U.S. Treasury securities and obligations of U.S. government corporations and agencies
Investments:
Assets measured at fair value	0	0
Level III | Available-for-sale | Corporate securities
Investments:
Assets measured at fair value	0	0
Level III | Available-for-sale | Municipal securities
Investments:
Assets measured at fair value	0	0
Level III | Available-for-sale | Short-term time deposits
Investments:
Assets measured at fair value	0
Level III | Available-for-sale | Asset-backed securities
Investments:
Assets measured at fair value	0	0
Level III | Available-for-sale | Residential mortgage-backed securities
Investments:
Assets measured at fair value	0	0
Level III | Available-for-sale | Commercial mortgage-backed securities
Investments:
Assets measured at fair value	0	0
Level III | Restricted Deposits
Investments:
Assets measured at fair value	0	0
Level III | Restricted Deposits | U.S. Treasury securities and obligations of U.S. government corporations and agencies
Investments:
Assets measured at fair value	0	0
Level III | Restricted Deposits | Corporate securities
Investments:
Assets measured at fair value	0	0
Level III | Restricted Deposits | Municipal securities
Investments:
Assets measured at fair value	0	0
Level III | Restricted Deposits | Cash and cash equivalents
Investments:
Assets measured at fair value	0	0
Level III | Restricted Deposits | Certificates of deposit
Investments:
Assets measured at fair value	$ 0	0
Level III | Other long-term assets: | Interest rate swap agreements
Other long-term assets:
Derivative asset		$ 0

Fair Value Measurements - Narra

Fair Value Measurements - Narrative (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Aggregate carrying amount of life insurance contracts and equity investments, fair value	$ 950	$ 812

Medical Claims Liability - Sche

Medical Claims Liability - Schedule of Change in Medical Claims Liability (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Balance, January 1	$ 7,473	$ 6,831
Less: Reinsurance recoverable	20	27
Balance, January 1, net	7,453	6,804
Acquisitions and divestitures	3,872	57
Incurred related to:
Current year	64,105	44,283
Prior years	(446)	(641)
Total incurred	63,659	43,642
Paid related to:
Current year	56,074	36,972
Prior years	6,032	5,577
Total paid	62,106	42,549
Balance at September 30, net	12,878	7,954
Plus: Reinsurance recoverable	21	21
Balance, September 30	$ 12,899	$ 7,975

Medical Claims Liability - Narr

Medical Claims Liability - Narrative (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Insurance [Abstract]
Amounts recorded as an adjustment to premium revenues related to minimum HBR and return of premium programs	$ 97	$ 64
Short-duration insurance contracts, Incurred but not reported and expected development on reported claims	$ 8,307

Affordable Care Act - Net Recei

Affordable Care Act - Net Receivables (Payables) for Each of the Ongoing Programs (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Affordable Care Act [Abstract]
Risk adjustment receivable	$ 400	$ 245
Risk adjustment payable	(1,038)	(1,239)
Risk corridor receivable	457	4
Minimum medical loss ratio	(195)	(367)
Cost sharing reduction receivable	122	73
Cost sharing reduction payable	$ (1)	$ (1)

Affordable Care Act - Additiona

Affordable Care Act - Additional information (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
	Jul. 31, 2020	Sep. 30, 2020	Jun. 30, 2020
Affordable Care Act [Abstract]
Risk adjustment reduction to net payables	$ 94
Risk adjustment and reinsurance pre tax benefit			$ 63
Corridor receivable settlement, pre tax benefit		$ 398

Debt - Schedule of Debt (Detail

Debt - Schedule of Debt (Details) - USD ($)	Sep. 30, 2020	May 31, 2020	Feb. 29, 2020	Jan. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Fair value of interest rate swap agreements	$ 0				$ (1,000,000)
Total senior notes	15,060,000,000				12,010,000,000
Mortgage notes payable	51,000,000				54,000,000
Construction loan payable	177,000,000				140,000,000
Finance leases and other	137,000,000				122,000,000
Debt issuance costs	(142,000,000)				(143,000,000)
Total debt	16,826,000,000				13,726,000,000
Less current portion	(89,000,000)				(88,000,000)
Long-term debt	16,737,000,000				13,638,000,000
Revolving credit agreement
Debt Instrument [Line Items]
Credit facility	93,000,000				93,000,000
Senior Notes
Debt Instrument [Line Items]
Debt, face amount			$ 2,100,000,000
Term loan credit facility
Debt Instrument [Line Items]
Credit facility	1,450,000,000				1,450,000,000
$1,000 million 4.75% Senior Notes, due May 15, 2022 | Senior Notes
Debt Instrument [Line Items]
Debt, face amount	$ 1,000,000,000			$ 1,000,000,000
Interest rate	4.75%			4.75%
Senior notes	$ 1,005,000,000				1,004,000,000
$1,000 million 6.125% Senior Notes, due February 15, 2024 | Senior Notes
Debt Instrument [Line Items]
Debt, face amount					$ 1,000,000,000
Interest rate			6.125%		6.125%
Senior notes	0				$ 1,000,000,000
$2,200 million 4.75% Senior Notes, due January 15, 2025 | Senior Notes
Debt Instrument [Line Items]
Debt, face amount	$ 2,200,000,000		$ 2,200,000,000
Interest rate	4.75%		4.75%
Senior notes	$ 2,233,000,000				2,228,000,000
$1,200 million 5.25% Senior Notes due April 1, 2025 | Senior Notes
Debt Instrument [Line Items]
Debt, face amount	$ 1,200,000,000
Interest rate	5.25%
Senior notes	$ 1,245,000,000				0
$1,800 million 5.375% Senior Notes, due June 1, 2026 | Senior Notes
Debt Instrument [Line Items]
Debt, face amount	$ 1,800,000,000
Interest rate	5.375%
Senior notes	$ 1,800,000,000				1,800,000,000
$750 million 5.375% Senior Notes due August 15, 2026 | Senior Notes
Debt Instrument [Line Items]
Debt, face amount	$ 750,000,000
Interest rate	5.375%
Senior notes	$ 796,000,000				0
$2,500 million 4.25% Senior Notes due December 15, 2027 | Senior Notes
Debt Instrument [Line Items]
Debt, face amount	$ 2,500,000,000	$ 2,500,000,000
Interest rate	4.25%	4.25%
Senior notes	$ 2,481,000,000				2,479,000,000
$3,500 million 4.625% Senior Notes due December 15, 2029 | Senior Notes
Debt Instrument [Line Items]
Debt, face amount	$ 3,500,000,000	$ 3,500,000,000
Interest rate	4.625%	4.625%
Senior notes	$ 3,500,000,000				3,500,000,000
$2,000 million 3.375% Senior Notes due February 15, 2030 | Senior Notes
Debt Instrument [Line Items]
Debt, face amount	$ 2,000,000,000	$ 2,000,000,000	$ 2,000,000,000
Interest rate	3.375%	3.375%	3.375%
Senior notes	$ 2,000,000,000				$ 0

Debt - Narrative (Details)

Debt - Narrative (Details)	1 Months Ended	3 Months Ended			9 Months Ended
	Feb. 29, 2020USD ($)derivative	Dec. 31, 2020USD ($)	Sep. 30, 2020USD ($)	Sep. 30, 2019USD ($)	Sep. 30, 2020USD ($)	Sep. 30, 2019USD ($)	Oct. 31, 2020USD ($)	May 31, 2020USD ($)	Jan. 31, 2020USD ($)	Jan. 23, 2020USD ($)	Dec. 31, 2019USD ($)
Debt Instrument [Line Items]
Loss on extinguishment of debt	$ 44,000,000		$ 0	$ 0	$ 44,000,000	$ 0
Number of Interest rate swap contracts terminated | derivative	3
Proceeds from termination of interest rate swaps	$ 9,000,000
Subsequent Event
Debt Instrument [Line Items]
Loss on extinguishment of debt		$ 17,000,000
Interest Rate Swap
Debt Instrument [Line Items]
Derivative notional amount	1,000,000,000
Interest Rate Contracts- Swap
Debt Instrument [Line Items]
Derivative notional amount	2,100,000,000
Senior Notes
Debt Instrument [Line Items]
Debt, face amount	2,100,000,000
Senior Notes | $1,200 Million Senior Notes Due April 2025
Debt Instrument [Line Items]
Debt, face amount			$ 1,200,000,000		$ 1,200,000,000
Interest rate			5.25%		5.25%
Senior Notes | $1,200 Million Senior Notes Due April 2025 | Subsequent Event
Debt Instrument [Line Items]
Debt, face amount							$ 1,200,000,000
Interest rate							5.25%
Senior Notes | $750 million 5.375% Senior Notes Due August 2026
Debt Instrument [Line Items]
Debt, face amount			$ 750,000,000		$ 750,000,000
Interest rate			5.375%		5.375%
Senior Notes | 3.375% Senior Notes Due 2030
Debt Instrument [Line Items]
Debt, face amount	$ 2,000,000,000		$ 2,000,000,000		$ 2,000,000,000			$ 2,000,000,000
Interest rate	3.375%		3.375%		3.375%			3.375%
Senior Notes | $1,000 million 6.125% Senior Notes, due February 15, 2024
Debt Instrument [Line Items]
Debt, face amount											$ 1,000,000,000
Interest rate	6.125%										6.125%
Debt redemption amount	$ 1,000,000,000
Senior Notes | $1,000 million 4.75% Senior Notes, due May 15, 2022
Debt Instrument [Line Items]
Debt, face amount			$ 1,000,000,000		$ 1,000,000,000				$ 1,000,000,000
Interest rate			4.75%		4.75%				4.75%
Senior Notes | $1,000 million 4.75% Senior Notes due January 15, 2025
Debt Instrument [Line Items]
Debt, face amount								$ 1,000,000,000
Interest rate								4.75%
Senior Notes | $2,500 million 4.25% Senior Notes due December 15, 2027
Debt Instrument [Line Items]
Debt, face amount			$ 2,500,000,000		$ 2,500,000,000			$ 2,500,000,000
Interest rate			4.25%		4.25%			4.25%
Senior Notes | $3,500 million 4.625% Senior Notes due December 15, 2029
Debt Instrument [Line Items]
Debt, face amount			$ 3,500,000,000		$ 3,500,000,000			$ 3,500,000,000
Interest rate			4.625%		4.625%			4.625%
Senior Notes | $2,200 Million 3.0% Senior Notes due October 2030 [Member] | Subsequent Event
Debt Instrument [Line Items]
Debt, face amount							$ 2,200,000,000
Interest rate							3.00%
Senior Notes | $2,200 million 4.75% Senior Notes, due January 15, 2025
Debt Instrument [Line Items]
Debt, face amount	$ 2,200,000,000		$ 2,200,000,000		$ 2,200,000,000
Interest rate	4.75%		4.75%		4.75%
WellCare Health Plans, Inc.
Debt Instrument [Line Items]
Acquisition of WellCare Notes										$ 2,055,000,000
WellCare Health Plans, Inc. | Senior Notes | $1,200 Million Senior Notes Due April 2025
Debt Instrument [Line Items]
Debt, face amount									$ 1,200,000,000
Interest rate									5.25%
WellCare Health Plans, Inc. | Senior Notes | $750 million 5.375% Senior Notes Due August 2026
Debt Instrument [Line Items]
Debt, face amount									$ 750,000,000
Interest rate									5.375%
WellCare Health Plans, Inc. | Senior Notes | $1,146 Million 5.25% Senior Notes Due 2025
Debt Instrument [Line Items]
Debt, face amount									$ 1,146,000,000
Interest rate									5.25%
WellCare Health Plans, Inc. | Senior Notes | 5.375% Senior Notes Due 2026
Debt Instrument [Line Items]
Debt, face amount									$ 747,000,000
Interest rate									5.375%

Leases - Narrative (Details)

Leases - Narrative (Details) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2020USD ($)	Sep. 30, 2020USD ($)lease	Jan. 23, 2020USD ($)
Lessee, Lease, Description [Line Items]
Operating lease expense	$ 68	$ 202
Lease liabilities reduced by cash paid	67	198
ROU assets from new operating leases in exchange for lease liability	55	55
Liability from new operating leases	$ 114	114
Operating leases not yet commenced		$ 52
Operating leases not yet commenced, number of significant leases executed | lease		1
Lease terms	10 years	10 years
ROU assets acquired	$ 1,088	$ 1,088
Lease liability acquired	$ 1,237	$ 1,237
Weighted average remaining lease term	8 years 6 months	8 years 6 months
Weighted-average discount rate for operating leases	3.70%	3.70%
WellCare Health Plans, Inc.
Lessee, Lease, Description [Line Items]
ROU assets acquired			$ 300
Lease liability acquired			$ 300

Leases - ROU Assets and Liabili

Leases - ROU Assets and Liabilities (Details) $ in Millions	Sep. 30, 2020USD ($)
Assets
Operating Lease, Right-of-Use Asset	$ 1,088
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	us-gaap:OtherAssetsNoncurrent
Liabilities
Short-term (recorded within accounts payable and accrued expenses)	$ 198
Long-term (recorded within other long-term liabilities)	1,039
Total lease liabilities	$ 1,237
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	us-gaap:OtherLiabilitiesNoncurrent

Leases - Operating Lease Paymen

Leases - Operating Lease Payments Over Next Five Years (Details) $ in Millions	Sep. 30, 2020USD ($)
Leases [Abstract]
2020	$ 49
2021	250
2022	210
2023	176
2024	150
2025	115
Thereafter	514
Total lease payments	1,464
Less: imputed interest	(227)
Total lease liabilities	$ 1,237

Stockholders' Equity (Details)

Stockholders' Equity (Details) - USD ($) shares in Thousands, $ in Millions	Jan. 23, 2020	Jan. 31, 2020	Mar. 31, 2020	Sep. 30, 2020	Sep. 30, 2019
Business Acquisition [Line Items]
Common stock repurchases				$ 570	$ 41
Remaining number of shares available under the program (in shares)				5,488
Stock Repurchase Program
Business Acquisition [Line Items]
Common stock repurchases (in shares)			8,672
Common stock repurchases			$ 500
WellCare Health Plans, Inc.
Business Acquisition [Line Items]
Shares issued (in shares)	171,000	171,000
Consideration transferred, shares valued	$ 11,431	$ 11,431
Cash paid	6,079
Consideration transferred related to fair value of replacement equity awards associated with pre-combination service	$ 95

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Earnings attributable to Centene Corporation
Earnings attributable to Centene Corporation	$ 568	$ 95	$ 1,820	$ 1,112
Shares used in computing per share amounts:
Weighted average number of common shares outstanding (in shares)	579,510	413,616	567,586	413,302
Common stock equivalents (as determined by applying the treasury stock method) (in shares)	8,461	6,340	8,146	6,398
Weighted average number of common shares and potential dilutive common shares outstanding (in shares)	587,971	419,956	575,732	419,700
Net earnings per common share attributable to Centene Corporation:
Basic earnings per common share (in dollars per share)	$ 0.98	$ 0.23	$ 3.21	$ 2.69
Diluted earnings per common share (in dollars per share)	$ 0.97	$ 0.23	$ 3.16	$ 2.65
Anti-dilutive restricted stock and restricted stock units excluded from the calculation of diluted earnings per common share (in shares)	64	1,532	75	1,424

Segment Information (Details)

Segment Information (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020USD ($)	Sep. 30, 2019USD ($)	Sep. 30, 2020USD ($)segment	Sep. 30, 2019USD ($)
Segment Reporting [Abstract]
Number of operating segments | segment			2
Segment Reporting Information [Line Items]
Total revenues	$ 29,090	$ 18,976	$ 82,827	$ 55,776
Earnings from operations	861	176	3,067	1,504
Eliminations
Segment Reporting Information [Line Items]
Total revenues	(3,091)	(2,719)	(9,125)	(7,797)
Managed Care
Segment Reporting Information [Line Items]
Total revenues	28,118	18,131	79,894	53,399
Earnings from operations	888	385	3,014	1,587
Managed Care | Operating Segments
Segment Reporting Information [Line Items]
Total revenues	28,014	18,087	79,573	53,283
Managed Care | Eliminations
Segment Reporting Information [Line Items]
Total revenues	104	44	321	116
Specialty Services
Segment Reporting Information [Line Items]
Total revenues	4,063	3,564	12,058	10,174
Earnings from operations	(27)	(209)	53	(83)
Specialty Services | Operating Segments
Segment Reporting Information [Line Items]
Total revenues	1,076	889	3,254	2,493
Specialty Services | Eliminations
Segment Reporting Information [Line Items]
Total revenues	$ 2,987	$ 2,675	$ 8,804	$ 7,681