Centene (CNC) 10-K 21 Feb 17 2016 FY Annual report Financial data

Document And Entity Information

Document And Entity Information - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2016	Feb. 17, 2017	Jun. 30, 2016
Document and Entity Information [Abstract]
Entity Registrant Name	CENTENE CORP
Entity Central Index Key	1,071,739
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 31, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	FY
Amendment Flag	false
Public Float			$ 12.2
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Common Stock, Shares Outstanding		172,028,161

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 3,930	$ 1,760
Premium and related receivables	3,098	1,279
Short term investments	505	176
Other current assets	832	390
Total current assets	8,365	3,605
Long term investments	4,545	1,927
Restricted deposits	138	115
Property, software and equipment, net	797	518
Goodwill	4,712	842
Intangible assets, net	1,545	155
Other long term assets	95	177
Total assets	20,197	7,339
Current liabilities:
Medical claims liability	3,929	2,298
Accounts payable and accrued expenses	3,763	976
Return of premium payable	614	207
Unearned revenue	313	143
Current portion of long term debt	4	5
Total current liabilities	8,623	3,629
Long term debt	4,651	1,216
Other long term liabilities	869	170
Total liabilities	14,143	5,015
Commitments and contingencies
Redeemable noncontrolling interests	145	156
Stockholders’ equity:
Preferred stock, $.001 par value; authorized 10,000,000 shares; no shares issued or outstanding at December 31, 2016 and December 31, 2015	0	0
Common stock, $.001 par value; authorized 400,000,000 shares; 178,134,306 issued and 171,919,071 outstanding at December 31, 2016, and 126,855,477 issued and 120,342,981 outstanding at December 31, 2015	0	0
Additional paid-in capital	4,190	956
Accumulated other comprehensive loss	(36)	(10)
Retained earnings	1,920	1,358
Treasury stock, at cost (6,215,235 and 6,512,496 shares, respectively)	(179)	(147)
Total Centene stockholders’ equity	5,895	2,157
Noncontrolling interest	14	11
Total stockholders’ equity	5,909	2,168
Total liabilities and stockholders’ equity	$ 20,197	$ 7,339

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2016	Dec. 31, 2015
Stockholders' equity:
Preferred stock, par value (in usd per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	400,000,000	400,000,000
Common stock, shares issued	178,134,306	126,855,477
Common stock, shares outstanding	171,919,071	120,342,981
Treasury stock, at cost	6,215,235	6,512,496

Consolidated Statements Of Oper

Consolidated Statements Of Operations - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenues:
Premium	$ 35,399	$ 19,389	$ 14,198
Service	2,180	1,876	1,469
Premium and service revenues	37,579	21,265	15,667
Premium tax and health insurer fee	3,028	1,495	893
Total revenues	40,607	22,760	16,560
Expenses:
Medical costs	30,636	17,242	12,678
Cost of services	1,864	1,621	1,280
Selling, general and administrative expenses	3,676	1,802	1,298
Amortization of acquired intangible assets	147	24	16
Premium tax expense	2,563	1,151	698
Health insurer fee expense	461	215	126
Total operating expenses	39,347	22,055	16,096
Earnings from operations	1,260	705	464
Other income (expense):
Investment and other income	114	35	28
Interest expense	(217)	(43)	(35)
Earnings from continuing operations, before income tax expense	1,157	697	457
Income tax expense	599	339	196
Earnings from continuing operations, net of income tax expense	558	358	261
Discontinued operations, net of income tax expense (benefit) of $2, $(1), and $1, respectively	3	(1)	3
Net earnings	561	357	264
(Earnings) loss attributable to noncontrolling interests	1	(2)	7
Net earnings	562	355	271
Amounts attributable to Centene Corporation common shareholders:
Earnings from continuing operations, net of tax	559	356	268
Discontinued operations, net of tax	3	(1)	3
Net earnings	$ 562	$ 355	$ 271
Basic:
Continuing operations (in usd per share)	$ 3.50	$ 2.99	$ 2.30
Discontinued operations (in usd per share)	0.02	(0.01)	0.03
Basic earnings per common share	3.52	2.98	2.33
Diluted:
Continuing operations (in usd per share)	3.41	2.89	2.23
Discontinued operations (in usd per share)	0.02	(0.01)	0.02
Diluted earnings per common share	$ 3.43	$ 2.88	$ 2.25
Weighted average number of common shares outstanding:
Basic (in shares)	159,567,607	119,100,744	116,345,764
Diluted (in shares)	163,975,407	123,066,370	120,360,212

Consolidated Statements of Ope5

Consolidated Statements of Operations (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Statement [Abstract]
Discontinued operations, income tax expense (benefit)	$ 2	$ (1)	$ 1

Consolidated Statement Of Compr

Consolidated Statement Of Comprehensive Earnings - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Comprehensive Income [Abstract]
Net earnings	$ 561	$ 357	$ 264
Reclassification adjustment, net of tax	(2)	0	0
Change in unrealized gain (loss) on investments, net of tax	(22)	(4)	3
Defined benefit pension plan net gain arising during the period, net of tax	1	0	0
Foreign currency translation adjustments, net of tax	(3)	(5)	(1)
Other comprehensive earnings (loss)	(26)	(9)	2
Comprehensive earnings	535	348	266
Comprehensive (earnings) loss attributable to the noncontrolling interests	1	(2)	7
Comprehensive earnings attributable to Centene Corporation	$ 536	$ 346	$ 273

Consolidated Statement Of Stock

Consolidated Statement Of Stockholders' Equity - USD ($) $ in Millions	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Treasury Stock	Non controlling Interest
Balance at Dec. 31, 2013	$ 1,243	$ 0	$ 594	$ (3)	$ 732	$ (89)	$ 9
Balance (in shares) at Dec. 31, 2013		117,346,430				6,707,952
Comprehensive Earnings:
Net earnings	270				271		(1)
Other comprehensive earnings (loss), net of tax	2			2
Common stock issued for acquisitions	190	$ 0	170			$ 20
Common stock issued for acquisitions (in shares)		(4,486,434)				(1,492,738)
Common stock issued for employee benefit plans	9	$ 0	9
Common stock issued for employee benefit plans (in shares)		2,442,000
Common stock repurchases	(29)					$ (29)
Common stock repurchases (in shares)						626,234
Stock compensation expense	48		48
Excess tax benefit from stock compensation	19		19
Contribution from noncontrolling interest							0
Reclassification to redeemable noncontrolling interest	(9)						(9)
Balance at Dec. 31, 2014	1,743	$ 0	840	(1)	1,003	$ (98)	(1)
Balance (in shares) at Dec. 31, 2014		124,274,864				5,841,448
Comprehensive Earnings:
Net earnings	355				355		0
Other comprehensive earnings (loss), net of tax	(9)			(9)
Common stock issued for acquisitions	12	$ 0	8			$ 4
Common stock issued for acquisitions (in shares)		0				(247,580)
Common stock issued for employee benefit plans	12	$ 0	12
Common stock issued for employee benefit plans (in shares)		2,580,613
Common stock repurchases	$ (53)					$ (53)
Common stock repurchases (in shares)	918,628					918,628
Stock compensation expense	$ 71		71
Excess tax benefit from stock compensation	25		25
Contribution from noncontrolling interest	11						11
Reclassification to redeemable noncontrolling interest	1						1
Balance at Dec. 31, 2015	$ 2,168	$ 0	956	(10)	1,358	$ (147)	11
Balance (in shares) at Dec. 31, 2015	120,342,981	126,855,477				6,512,496
Comprehensive Earnings:
Net earnings	$ 563				562		1
Other comprehensive earnings (loss), net of tax	(26)			(26)
Common stock issued for acquisitions	3,105	$ 0	3,074			$ 31
Common stock issued for acquisitions (in shares)		(48,218,310)				(1,375,596)
Common stock issued for employee benefit plans	12	$ 0	12
Common stock issued for employee benefit plans (in shares)		3,060,519
Common stock repurchases	$ (63)					$ (63)
Common stock repurchases (in shares)	1,078,335					1,078,335
Stock compensation expense	$ 148		148
Contribution from noncontrolling interest	2						2
Reclassification to redeemable noncontrolling interest	0
Balance at Dec. 31, 2016	$ 5,909	$ 0	$ 4,190	$ (36)	$ 1,920	$ (179)	$ 14
Balance (in shares) at Dec. 31, 2016	171,919,071	178,134,306				6,215,235

Consolidated Statements Of Stoc

Consolidated Statements Of Stockholders' Equity (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Stockholders' Equity [Abstract]
Tax on unrealized investment gain	$ (14)	$ 3	$ 1

Consolidated Statements Of Cash

Consolidated Statements Of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash flows from operating activities:
Net earnings	$ 561	$ 357	$ 264
Adjustments to reconcile net earnings to net cash provided by operating activities
Depreciation and amortization	278	111	89
Stock compensation expense	148	71	48
Debt extinguishment costs	(7)	0	0
Deferred income taxes	92	(17)	(42)
Gain on contingent consideration	(5)	(44)	0
Goodwill and intangible adjustment	0	38	0
Changes in assets and liabilities
Premium and related receivables	74	(360)	(463)
Other assets	167	(102)	(7)
Medical claims liabilities	145	536	609
Unearned revenue	43	(27)	129
Accounts payable and accrued expenses	402	39	506
Other long term liabilities	(61)	51	89
Other operating activities	14	5	1
Net cash provided by operating activities	1,851	658	1,223
Cash flows from investing activities:
Capital expenditures	(306)	(150)	(103)
Purchases of investments	(2,450)	(1,321)	(1,015)
Sales and maturities of investments	1,656	669	406
Investments in acquisitions, net of cash acquired	(1,297)	(18)	(136)
Other investing activities, net	0	7	0
Net cash used in investing activities	(2,397)	(813)	(848)
Cash flows from financing activities:
Proceeds from borrowings	8,946	1,925	1,875
Payment of long term debt	(6,076)	(1,583)	(1,674)
Common stock repurchases	(63)	(53)	(29)
Debt issue costs	(76)	(4)	(7)
Other financing activities, net	(14)	20	33
Net cash provided by financing activities	2,717	305	198
Effect of exchange rate changes on cash and cash equivalents	(1)	0	(1)
Net increase in cash and cash equivalents	2,170	150	572
Cash and cash equivalents, beginning of period	1,760	1,610	1,038
Cash and cash equivalents, end of period	3,930	1,760	1,610
Supplemental disclosures of cash flow information:
Interest paid	165	55	40
Income taxes paid	556	328	237
Equity issued in connection with acquisitions	$ 3,105	$ 12	$ 190

Organization And Operations

Organization And Operations	12 Months Ended
	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Operations	Organization and Operations Centene Corporation, or the Company, is a diversified, multi-national healthcare enterprise operating in two segments: Managed Care and Specialty Services. The Managed Care segment provides Medicaid and Medicaid-related health plan coverage to individuals through the government subsidized programs, including Medicaid, the State Children's Health Insurance Program (CHIP), Long Term Care (LTC), Foster Care, dual-eligible individuals (Duals) in Medicare Special Needs Plans and the Supplemental Security Income Program, also known as the Aged, Blind or Disabled Program (ABD), Medicare, and the Health Insurance Marketplace. The Company also offers a variety of individual, small group, and large group commercial health care products, both to employers and directly to members in the Managed Care segment. The Specialty Services segment consists of our specialty companies offering auxiliary healthcare services and products to state programs, correctional facilities, healthcare organizations, employer groups and other commercial organizations, as well as to our own subsidiaries. The Specialty Service segment also includes the Government Contracts business which includes the Company's government-sponsored managed care support contract with the U.S. Department of Defense (DoD) under the TRICARE program in the North Region, the Military Family and Life Counseling (MFLC) contract with the DoD, and other health care related government contracts, including the Patient Centered Community Care (PC3) contract with the U.S. Department of Veterans Affairs (VA). On March 24, 2016, the Company acquired all of the issued and outstanding shares of Health Net, Inc. (Health Net) a publicly traded managed care organization that delivers health care services through health plans and government-sponsored managed care plans. The transaction was valued at approximately $5,990 million , including the assumption of $703 million of outstanding debt. The acquisition allows the Company to offer a more comprehensive and scalable portfolio of solutions and provides opportunity for additional growth across the combined company's markets. On February 2, 2015, the Board of Directors declared a two-for-one split of Centene's common stock in the form of a 100% stock dividend distributed February 19, 2015 to stockholders of record on February 12, 2015. All share and per share information presented in this Form 10-K has been adjusted for the two-for-one stock split.

Summary Of Significant Accounti

Summary Of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation The accompanying consolidated financial statements include the accounts of Centene Corporation and all majority owned subsidiaries and subsidiaries over which the Company exercises the power and control to direct activities significantly impacting financial performance. All material intercompany balances and transactions have been eliminated. The assets, liabilities and results of operations of Kentucky Spirit Health Plan (Kentucky Spirit) are classified as discontinued operations for all periods presented. Certain amounts in the consolidated financial statements and notes have been reclassified to conform to the 2016 presentation. These reclassifications have no effect on net earnings or stockholders' equity as previously reported. Use of Estimates The preparation of financial statements in conformity with generally accepted accounting principles in the United States, or GAAP, requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Future events and their effects cannot be predicted with certainty; accordingly, the accounting estimates require the exercise of judgment. The accounting estimates used in the preparation of the consolidated financial statements will change as new events occur, as more experience is acquired, as additional information is obtained and as the operating environment changes. The Company evaluates and updates its assumptions and estimates on an ongoing basis and may employ outside experts to assist in our evaluation, as considered necessary. Actual results could differ from those estimates. Business Combinations Business combinations are accounted for using the acquisition method of accounting. The Company allocates the fair value of purchase consideration to the assets acquired and liabilities assumed based on their fair values at the acquisition date. The excess of the fair value of consideration transferred over the fair value of the net assets acquired is recorded as goodwill. Goodwill is generally attributable to the value of the synergies between the combined companies and the value of the acquired assembled workforce, neither of which qualifies for recognition as an intangible asset. The Company uses its best estimates and assumptions to value assets acquired and liabilities assumed at the acquisition date; however, these estimates are sometimes preliminary and in some instances, all information required to value the assets acquired and liabilities assumed may not be available or final as of the end of a reporting period subsequent to the business combination. If the accounting for the business combination is incomplete, provisional amounts are recorded. The provisional amounts are updated during the period determined, up to one year from the acquisition date. The Company includes the results of operations of acquired businesses in the Company's consolidated results prospectively from the date of acquisition. Acquisition related expenses and post-acquisition restructuring costs are recognized separately from the business combination and are expensed as incurred. Cash and Cash Equivalents Investments with original maturities of three months or less are considered to be cash equivalents. Cash equivalents consist of money market funds and bank certificates of deposit and savings accounts. The Company maintains amounts on deposit with various financial institutions, which may exceed federally insured limits. However, management periodically evaluates the credit-worthiness of those institutions, and the Company has not experienced any losses on such deposits. Investments Short term investments include securities with maturities greater than three months to one year. Long term investments include securities with maturities greater than one year. Short term and long term investments are generally classified as available for sale and are carried at fair value. Certain equity investments are recorded using the cost or equity method. Unrealized gains and losses on investments available for sale are excluded from earnings and reported in accumulated other comprehensive income, a separate component of stockholders' equity, net of income tax effects. Premiums and discounts are amortized or accreted over the life of the related security using the effective interest method. The Company monitors the difference between the cost and fair value of investments. Investments that experience a decline in value that is judged to be other than temporary are written down to fair value and a realized loss is recorded in investment and other income. To calculate realized gains and losses on the sale of investments, the Company uses the specific amortized cost of each investment sold. Realized gains and losses are recorded in investment and other income. The Company uses the equity method to account for its investments in entities that it does not control but has the ability to exercise significant influence over operating and financial policies. These investments are recorded at the lower of their cost or fair value adjusted for the Company's proportionate share of earnings or losses. Restricted Deposits Restricted deposits consist of investments required by various state statutes to be deposited or pledged to state agencies. These investments are classified as long term, regardless of the contractual maturity date, due to the nature of the states' requirements. The Company is required to annually adjust the amount of the deposit pledged to certain states. Fair Value Measurements In the normal course of business, the Company invests in various financial assets and incurs various financial liabilities. Fair values are disclosed for all financial instruments, whether or not such values are recognized in the Consolidated Balance Sheets. Management obtains quoted market prices and other observable inputs for these disclosures. The carrying amounts reported in the Consolidated Balance Sheets for cash and cash equivalents, premium and related receivables, medical claims liability, accounts payable and accrued expenses, unearned revenue, and certain other current assets and liabilities are carried at cost, which approximates fair value because of their short term nature. The following methods and assumptions were used to estimate the fair value of each financial instrument: • Available for sale investments and restricted deposits: The carrying amount is stated at fair value, based on quoted market prices, where available. For securities not actively traded, fair values were estimated using values obtained from independent pricing services or quoted market prices of comparable instruments. • Senior unsecured notes: Estimated based on third-party quoted market prices for the same or similar issues. • Variable rate debt: The carrying amount of our floating rate debt approximates fair value since the interest rates adjust based on market rate adjustments. • Interest rate swap: Estimated based on third-party market prices based on the forward 3-month LIBOR curve. • Contingent consideration: Estimated based on expected achievement of metrics included in the acquisition agreement considering circumstances that exist as of the acquisition date. Property, Software and Equipment Property, software and equipment are stated at cost less accumulated depreciation. Capitalized software includes certain costs incurred in the development of internal-use software, including external direct costs of materials and services and payroll costs of employees devoted to specific software development. Depreciation is calculated principally by the straight-line method over estimated useful lives. Leasehold improvements are depreciated using the straight-line method over the shorter of the expected useful life or the remaining term of the lease. Property, software and equipment are depreciated over the following periods: Fixed Asset Depreciation Period Buildings and land improvements 5 - 40 years Computer hardware and software 2 - 7 years Furniture and equipment 3 - 10 years Land improvements 3 - 20 years Leasehold improvements 1 - 20 years The carrying amounts of all long-lived assets are evaluated to determine if adjustment to the depreciation and amortization period or to the unamortized balance is warranted. Such evaluation is based principally on the expected utilization of the long-lived assets. The Company retains fully depreciated assets in property and accumulated depreciation accounts until it removes them from service. In the case of sale, retirement, or disposal, the asset cost and related accumulated depreciation balance is removed from the respective account, and the resulting net amount, less any proceeds, is included as a component of earnings from operations in the Consolidated Statements of Operations. Goodwill and Intangible Assets Intangible assets represent assets acquired in purchase transactions and consist primarily of purchased contract rights, provider contracts, customer relationships, trade names, developed technologies and goodwill. Intangible assets are amortized using the straight-line method over the following periods: Intangible Asset Amortization Period Purchased contract rights 5 - 15 years Provider contracts 4 - 15 years Customer relationships 3 - 15 years Trade names 1 - 20 years Developed technology 5 years The Company tests for impairment of intangible assets as well as long-lived assets whenever events or changes in circumstances indicate that the carrying value of an asset or asset group (hereinafter referred to as “asset group”) may not be recoverable by comparing the sum of the estimated undiscounted future cash flows expected to result from use of the asset group and its eventual disposition to the carrying value. Such factors include, but are not limited to, significant changes in membership, state funding, state contracts and provider networks and contracts. If the sum of the estimated undiscounted future cash flows is less than the carrying value, an impairment determination is required. The amount of impairment is calculated by subtracting the fair value of the asset group from the carrying value of the asset group. An impairment charge, if any, is recognized within earnings from operations. The Company tests goodwill for impairment using a fair value approach. The Company is required to test for impairment at least annually, absent a triggering event, which could include a significant decline in operating performance that would require an impairment assessment. Absent any impairment indicators, the Company performs its goodwill impairment testing during the fourth quarter of each year. The Company recognizes an impairment charge for any amount by which the carrying amount of goodwill exceeds its implied fair value. The Company first assesses qualitative factors to determine whether it is necessary to perform the two-step quantitative goodwill impairment test. The Company generally does not calculate the fair value of a reporting unit unless it determines, based on a qualitative assessment, that it is more likely than not that its fair value is less than its carrying amount. However, in certain circumstances, such as recent acquisitions, the Company may elect to perform a quantitative assessment without first assessing qualitative factors. If the two-step quantitative test is deemed necessary, the Company determines an appropriate valuation technique to estimate a reporting unit's fair value as of the testing date. The Company utilizes either the income approach or the market approach, whichever is most appropriate for the respective reporting unit. The income approach is based on an internally developed discounted cash flow model that includes many assumptions related to future growth rates, discount factors, future tax rates, etc. The market approach is based on financial multiples of comparable companies derived from current market data. Changes in economic and operating conditions impacting assumptions used in our analyses could result in goodwill impairment in future periods. Medical Claims Liability Medical claims liability includes claims reported but not yet paid, or inventory, estimates for claims incurred but not reported, or IBNR, and estimates for the costs necessary to process unpaid claims at the end of each period. The Company estimates its medical claims 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. Actuarial Standards of Practice generally require that the medical claims liability estimates be adequate to cover obligations under moderately adverse conditions. Moderately adverse conditions are situations in which the actual claims are expected to be higher than the otherwise estimated value of such claims at the time of estimate. In many situations, the claims amounts ultimately settled will be different than the estimate that satisfies the Actuarial Standards of Practice. The Company includes in its IBNR an estimate for medical claims liability under moderately adverse conditions which represents the risk of adverse deviation of the estimates in its actuarial method of reserving. The Company uses its judgment to determine the assumptions to be used in the calculation of the required estimates. The assumptions it considers when estimating IBNR include, without limitation, claims receipt and payment experience (and variations in that experience), changes in membership, provider billing practices, healthcare service utilization trends, cost trends, product mix, seasonality, prior authorization of medical services, benefit changes, known outbreaks of disease or increased incidence of illness such as influenza, provider contract changes, changes to fee schedules, and the incidence of high dollar or catastrophic claims. The Company's development of the medical claims liability estimate is a continuous process which it monitors and refines on a monthly basis as additional claims receipts and payment information becomes available. As more complete claims information becomes available, the Company adjusts the amount of the estimates, and includes the changes in estimates in medical costs in the period in which the changes are identified. In every reporting period, the operating results include the effects of more completely developed medical claims liability estimates associated with previously reported periods. The Company consistently applies its reserving methodology from period to period. As additional information becomes known, it adjusts the actuarial model accordingly to establish medical claims liability estimates. The Company periodically reviews actual and anticipated experience compared to the assumptions used to establish medical costs. The Company establishes premium deficiency reserves if actual and anticipated experience indicates that existing policy liabilities together with the present value of future gross premiums will not be sufficient to cover the present value of future benefits, settlement and maintenance costs. Revenue Recognition The Company's health plans generate revenues primarily from premiums received from the states in which it operates health plans. The Company generally receives a fixed premium per member per month pursuant to its state contracts and recognizes premium revenues during the period in which it is obligated to provide services to its members at the amount reasonably estimable. In some instances, the Company's base premiums are subject to an adjustment, or risk score, based on the acuity of its membership. Generally, the risk score is determined by the State analyzing submissions of processed claims data to determine the acuity of the Company's membership relative to the entire state's Medicaid membership. The Company estimates the amount of risk adjustment based upon the processed claims data submitted and expected to be submitted to Centers for Medicare and Medicaid Services (CMS) and records revenues on a risk adjusted basis. Some contracts allow for additional premiums related to certain supplemental services provided such as maternity deliveries. The Company's contracts with states may require us to maintain a minimum health benefits ratio (HBR) or may require us to share profits excess of certain levels. In certain circumstances, our plans may be required to return premium to the state in the event profits exceed established levels. We estimate the effect of these programs and recognize reductions in revenue in the current period. Other states may require us to meet certain performance and quality metrics in order to receive additional or full contractual revenue. For performance-based contracts, we do not recognize revenue subject to refund until data is sufficient to measure performance. Revenues are recorded based on membership and eligibility data provided by the states, which is adjusted on a monthly basis by the states for retroactive additions or deletions to membership data. These eligibility adjustments are estimated monthly and subsequent adjustments are made in the period known. The Company continuously reviews and updates those estimates as new information becomes available. It is possible that new information could require us to make additional adjustments, which could be significant, to these estimates. The Company's Medicare Advantage contracts are with CMS. CMS deploys a risk adjustment model which apportions premiums paid to all health plans according to health severity and certain demographic factors. The CMS risk adjustment model pays more for members whose medical history would indicate that they are expected to have higher medical costs. Under this risk adjustment methodology, CMS calculates the risk adjusted premium payment using diagnosis data from hospital inpatient, hospital outpatient, physician treatment settings as well as prescription drug events. The Company and the health care providers collect, compile and submit the necessary and available diagnosis data to CMS within prescribed deadlines. The Company estimates risk adjustment revenues based upon the diagnosis data submitted and expected to be submitted to CMS and records revenues on a risk adjusted basis. The Company's specialty services generate revenues under contracts with state and federal programs, healthcare organizations and other commercial organizations, as well as from our own subsidiaries. Revenues are recognized when the related services are provided or as ratably earned over the covered period of services. The Company recognizes revenue related to administrative services under the T-3 TRICARE government-sponsored managed care support contract in the North Region for the DoD's TRICARE program (T-3 contract) on a straight-line basis over the option period, when the fees become fixed and determinable. The T-3 contract includes various performance-based incentives and penalties. For each of the incentives or penalties, the Company adjusts revenue accordingly based on the amount that it has earned or incurred at each interim date and are legally entitled to in the event of a contract termination. Some states enact premium taxes, similar assessments and provider pass-through payments, collectively premium taxes, and these taxes are recorded as a separate component of both revenues and operating expenses. Additionally, the Company's insurance subsidiaries are subject to the Affordable Care Act annual health insurer fee (HIF). If the Company is able to negotiate reimbursement of portions of these premium taxes or the HIF, it recognizes revenue associated with the HIF on a straight-line basis when we have binding agreements for such reimbursements, including the “gross-up” to reflect the HIFs non-tax deductible nature. Collectively, this revenue is recorded as premium tax and health insurer fee revenue in the Consolidated Statements of Operations. Affordable Care Act The Affordable Care Act (ACA) established risk spreading premium stabilization programs effective January 1, 2014. These programs, commonly referred to as the “three Rs”, include a permanent risk adjustment program, a transitional reinsurance program, and a temporary risk corridor program. Additionally, the ACA established a minimum annual medical loss ratio (MLR) and cost-sharing reductions. Each of the three R programs are taken into consideration to determine if the Company's estimated annual medical costs are less than the minimum loss ratio and require an adjustment to premium revenue to meet the minimum MLR. During the second quarter of 2016, the Company recognized a $70 million net pre-tax benefit related to the reconciliation of 2015 risk adjustment and reinsurance programs. During the third quarter of 2016, the company received information from CMS, indicating that some of the participants in the Arizona risk adjustment program were unable to pay the amounts owed. As a result, the uncollected portion has been allocated pro-rata to other insurers in the market. Accordingly, the Company reduced the pre-tax earnings by $19 million during the third quarter. The Company’s accounting policies for the programs are as follows: Risk Adjustment The permanent risk adjustment program established by the ACA transfers funds from qualified individual and small group insurance plans with below average risk scores to those plans with above average risk scores within each state. The Company estimates the receivable or payable under the risk adjustment program based on its estimated risk score compared to the state average risk score. The Company may record a receivable or payable as an adjustment to Premium revenue to reflect the year to date impact of the risk adjustment based on its best estimate. The Company expects to refine its estimate as new information becomes available. As of December 31, 2016 and 2015 , the Company recorded a payable of $425 million and $108 million , respectively, associated with risk adjustment. Reinsurance The ACA established a transitional three-year reinsurance program whereby the Company’s claims costs incurred for qualified members will be reimbursed when they exceed a specific threshold. For the 2016 benefit year, qualified member claims that exceeded $90,000 entitled the Company to reimbursement from the programs at 50% coinsurance. The Company accounts for reinsurance recoveries as a reduction of Medical Costs based on each individual case that exceeds the reinsurance threshold established by the program. As of December 31, 2016 and 2015 , the Company recorded a receivable of $122 million and $24 million , respectively, associated with reinsurance. Risk Corridor The temporary, three-year risk corridor program established by the ACA applies to qualified individual and small group health plans operating both inside and outside of the Health Insurance Marketplace. The risk corridor program limits the Company’s gains and losses in the Health Insurance Marketplace by comparing certain medical and administrative costs to a target amount and sharing the risk for allowable costs with the federal government. Allowable medical costs are adjusted for risk adjustment settlements, transitional reinsurance recoveries, and cost sharing reductions received from the federal government. The Company records a risk corridor receivable or payable as an adjustment to premium revenue on a year to date basis based on where its estimated annual costs fall within the risk corridor range. As of December 31, 2016 and 2015 , the Company recorded a payable of $3 million and $4 million , respectively, associated with risk corridor. Minimum Medical Loss Ratio Additionally, the ACA established a minimum annual MLR for the Health Insurance Marketplace. Each of the three R programs described above are taken into consideration to determine if the Company’s estimated annual medical costs are less than the minimum loss ratio and require an adjustment to premium revenue to meet the minimum MLR. As of December 31, 2016 and 2015 , the Company recorded a payable of $18 million and $15 million , respectively, associated with minimum MLR. Cost-sharing Reductions (CSRs) The ACA directs issuers to reduce the Company's members' cost sharing for essential health benefits for individuals with Federal Poverty Levels (FPLs) between 100% and 250% who are enrolled in a silver tier product; eliminate cost sharing for Indians/Alaska Natives with an FPL less than 300% and eliminate cost sharing for Indians/Alaska Natives regardless of FPL level when services are provided by an Indian Health Service. In order to compensate issuers for reduced cost sharing provided to enrollees, CMS pays an advance CSR payment to the Company each month based on the Company’s certification data provided at the time of the qualified health plan application. After the close of the benefit year, the Company is required to provide CMS with data on the value of the CSRs provided to enrollees based on either a ‘simplified’ or ‘standard’ approach. A reconciliation will occur in order to calculate the difference between the Company’s CSR advance payments received and the value of CSRs provided to enrollees. This reconciliation will produce either a payable or receivable to/from CMS. The Company has elected the standard methodology approach. As of December 31, 2016 and 2015 , the Company recorded a payable of $147 million and $40 million , respectively, associated with CSRs. Premium and Related Receivables and Unearned Revenue Premium and service revenues collected in advance are recorded as unearned revenue. For performance-based contracts the Company does not recognize revenue subject to refund until data is sufficient to measure performance. Premiums and service revenues due to the Company are recorded as premium and related receivables and are recorded net of an allowance based on historical trends and management's judgment on the collectibility of these accounts. As the Company generally receives payments during the month in which services are provided, the allowance is typically not significant in comparison to total revenues and does not have a material impact on the presentation of the financial condition or results of operations. Amounts receivable under federal contracts are comprised primarily of contractually defined billings, accrued contract incentives under the terms of the contract and amounts related to change orders for services not originally specified in the contract. Activity in the allowance for uncollectible accounts for the years ended December 31, is summarized below ($ in millions): 2016 2015 2014 Allowances, beginning of year $ 10 $ 5 $ 1 Amounts charged to expense 33 12 8 Write-offs of uncollectible receivables (14 ) (7 ) (4 ) Allowances, end of year $ 29 $ 10 $ 5 Significant Customers Centene receives the majority of its revenues under contracts or subcontracts with state Medicaid managed care programs. The current contracts expire on various dates between February 28, 2017 and December 31, 2022. Customers where the aggregate annual contract revenues exceeded 10% of total annual revenues included the state of California, where the percentage of the Company's total revenue was 21% , 3% and 2% for the years ended December 31, 2016, 2015 and 2014 , respectively; the state of Florida, where the percentage of the Company's total revenue was 14% for the years ended December 31, 2015 and 2014; and the state of Texas, where the percentage of the Company's total revenue was 13% , 22% and 25% for the years ended December 31, 2016, 2015 and 2014 , respectively. The decrease in the revenue percentage for the state of Texas compared to prior periods is attributable to the overall growth in the Company's revenues as a result of the Health Net acquisition. Other Income (Expense) Other income (expense) consists principally of investment income, interest expense and equity method earnings from investments. Investment income is derived from the Company's cash, cash equivalents, restricted deposits and investments. Interest expense relates to borrowings under the senior notes, interest rate swap, credit facilities, interest on capital leases and credit facility fees. Income Taxes Deferred tax assets and liabilities are recorded for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax law or tax rates is recognized in income in the period that includes the enactment date. Valuation allowances are provided when it is considered more likely than not that deferred tax assets will not be realized. In determining if a deductible temporary difference or net operating loss can be realized, the Company considers future reversals of existing taxable temporary differences, future taxable income, taxable income in prior carryback periods and tax planning strategies. Contingencies The Company accrues for loss contingencies associated with outstanding litigation, claims and assessments for which it has determined it is probable that a loss contingency exists and the amount of loss can be reasonably estimated. The Company expenses professional fees associated with litigation claims and assessments as incurred. Stock Based Compensation The fair value of the Company's employee share options and similar instruments are estimated using the Black-Scholes option-pricing model. That cost is recognized over the period during which an employee is required to provide service in exchange for the award. Excess tax benefits related to stock compensation are presented as a cash inflow from financing activities for the years ended December 31, 2015 and 2014 and as a cash inflow from operating activities for the year ended December 31, 2016 due to the prospective adoption of employee share-based payment guidance in 2016. The Company accounts for forfeitures when they occur. Foreign Currency Translation The Company is exposed to foreign currency exchange risk through its equity method investment in Ribera Salud S.A. (Ribera Salud), a Spanish health management group whose functional currency is the Euro. The assets and liabilities of the Company's investment are translated into United States dollars at the balance sheet date. The Company translates its proportionate share of earnings using average rates during the year. The resulting foreign currency translation adjustments are recorded as a separate component of accumulated other comprehensive income. Recently Adopted Accounting Pronouncements In March 2016, the Financial Accounting Standards Board (FASB) issued an Accounting Standards Update (ASU) which simplifies several aspects of the accounting for employee share-based payment transactions, including the accounting for income taxes, forfeitures, and statutory tax withholding requirements, as well as classification in the statement of cash flows. Under the new guidance, an entity recognizes all excess tax benefits and tax deficiencies as income tax expense or benefit in the income statement. The ASU also allows an entity to elect as an accounting policy either to continue to estimate the total number of awards for which the requisite service period will not be rendered, as currently required, or to account for forfeitures when they occur. Finally, the ASU modifies the current exception to liability classification of an award when an employer uses a net-settlement feature to withhold shares to meet the employee's minimum statutory tax withholding requirement. The new standard is effective for annual periods beginning after December 15, 2016, including interim periods within those annual reporting periods. Early adoption is permitted. The Company elected to early adopt this guidance in the fourth quarter of 2016. The adoption of this ASU decreased the Company's income tax expense by $14 million in 2016 and increased diluted shares outstanding by approximately one million shares. Excess tax benefits related to stock compensation are now presented a

Health Net Merger

Health Net Merger	12 Months Ended
	Dec. 31, 2016
Business Combinations [Abstract]
Health Net	Health Net On March 24, 2016 , the Company acquired all of the issued and outstanding shares of Health Net, a publicly traded managed care organization that delivers health care services through health plans and government-sponsored managed care plans. The transaction was valued at approximately $5,990 million , including the assumption of $703 million of outstanding debt. The acquisition allows the Company to offer a more comprehensive and scalable portfolio of solutions and provides opportunity for additional growth across the combined company's markets. The total consideration for the acquisition was $5,287 million , consisting of Centene common shares valued at $3,038 million (based on Centene's stock price of $62.70 ), $2,247 million in cash, and $2 million related to the fair value adjustment to stock based compensation associated with pre-combination service. Each Health Net share was converted into 0.622 of a validly issued, fully paid, non-assessable share of Centene common stock and $28.25 in cash. In total, 48,449,444 shares of Centene common stock were issued in connection with the transaction. The cash portion of the acquisition consideration was funded through the issuance of long-term debt as further discussed in Note 11 , Debt . For the year ended December 31, 2016 , the Company also recognized acquisition related expenses of $234 million that were recorded in selling, general and administrative (SG&A) expense in the Consolidated Statements of Operations. The acquisition of Health Net has been accounted for as a business combination using the acquisition method of accounting which requires assets acquired and liabilities assumed to be recognized at fair value as of the acquisition date. The valuation of all the assets acquired and liabilities assumed was finalized in the fourth quarter of 2016. Since the initial allocation of purchase price, the Company made adjustments and reclassifications to the fair value of certain assets and liabilities acquired, including the premium and related receivables, medical claims liability, accrued liabilities, return of premium payable and deferred taxes, resulting in a net increase of $258 million to goodwill. The Company's allocation of the fair value of assets acquired and liabilities assumed as of the acquisition date of March 24, 2016 , is as follows ($ in millions): Assets Acquired and Liabilities Assumed Cash and cash equivalents $ 956 Premium and related receivables (a) 1,890 Short term investments 74 Other current assets 524 Long term investments 2,037 Restricted deposits 30 Property, software and equipment, net 41 Intangible assets (b) 1,530 Other long term assets 136 Total assets acquired 7,218 Medical claims liability (c) 1,482 Borrowings under revolving credit facility 285 Accounts payable and accrued expenses (c) (d) 2,297 Return of premium payable 435 Unearned revenue 130 Long term deferred tax liabilities (e) 311 Long term debt (f) 418 Other long term liabilities 432 Total liabilities assumed 5,790 Total identifiable net assets 1,428 Goodwill (g) 3,859 Total assets acquired and liabilities assumed $ 5,287 Significant fair value adjustments are noted as follows: (a) The fair value of premium and related receivables approximated their historical cost, with the exception of the risk corridor receivable associated with the Health Insurance Marketplace. The fair value of the risk corridor receivable was estimated at $9 million . (b) 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 is 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. Other valuation methods, including the market approach and cost approach, were also utilized in estimating the fair value of certain intangible assets. The Company has finalized its fair value of intangibles to be $1,530 million with a weighted average life of 12 years. This final fair value of intangibles is approximately $30 million higher than the preliminary fair value of intangibles and the weighted average life increased by two years, which resulted in an immaterial true-up of intangible amortization recorded during the fourth quarter of 2016. The Company identified intangible assets including purchased contract rights, provider contracts, trade names and developed technology. (c) Medical claims liability and accounts payable and accrued expenses include $160 million of reserves associated with substance abuse rehabilitation claims primarily related to periods prior to the acquisition date. (d) Accounts payable and accrued expenses include approximately $253 million related to premium deficiency reserves based on cost trends existing prior to the acquisition date. The premium deficiency reserves are primarily associated with losses in the individual commercial business, largely in California, unfavorable performance in the Arizona commercial business as well as unfavorable performance in the Medicare business primarily in Oregon and Arizona. (e) The deferred tax liabilities are presented net of $365 million of deferred tax assets. (f) Debt is required to be measured at fair value under the acquisition method of accounting. The fair value of Health Net's $400 million Senior Notes assumed in the acquisition was $418 million . The $18 million increase will be amortized as a reduction to interest expense over the remaining life of the debt. In November 2016, this debt was redeemed as discussed in Note 11 , Debt. (g) The acquisition resulted in $3,859 million of goodwill related primarily to buyer specific synergies expected from the acquisition and the assembled workforce of Health Net. This goodwill is not deductible for income tax purposes. The Company assigned $3,317 million of goodwill to the Managed Care segment and $542 million of goodwill to the Specialty Services segment. The 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 $ 1,095 13 Provider contracts 181 11 Trade names 150 10 Developed technology 104 5 Total intangible assets acquired $ 1,530 12 Statement of Operations From the acquisition date through December 31, 2016 , the Company's Consolidated Statements of Operations include total Health Net revenues of $13,454 million . It is impracticable to determine the effect on net income resulting from the Health Net acquisition for the year ended December 31, 2016 , as the Company immediately integrated Health Net into its ongoing operations. Unaudited Pro Forma Financial Information The unaudited pro forma total revenues for the year ended December 31, 2016 were $44,280 million . The following table presents supplemental pro forma information for the year ended December 31, 2015 ($ in millions, except per share data). December 31, 2015 Total revenues $ 38,826 Net earnings attributable to Centene Corporation $ 245 Diluted earnings per share $ 1.43 The pro forma results do not reflect any anticipated synergies, efficiencies, or other cost savings of the acquisition. Accordingly, the unaudited pro forma financial information is not indicative of the results if the acquisition had been completed on January 1, 2015 and is not a projection of future results. It is impracticable for the Company to determine the pro forma earnings information for the year ended December 31, 2016 due to the nature of obtaining that information as the Company immediately integrated Health Net into its ongoing operations. The unaudited pro forma financial information reflects the historical results of Centene and Health Net adjusted as if the acquisition had occurred on January 1, 2015, primarily for the following: • Additional interest income associated with adjusting the amortized cost of Health Net's investment portfolio to fair value. • Elimination of historical Health Net intangible asset amortization expense and addition of amortization expense based on the current values of identifiable intangible assets. • Adjustments to premium revenue related to the risk corridor receivables associated with the Health Insurance Marketplace to align with Centene's accounting policies. • Interest expense associated with financing the acquisition and amortization of the fair value adjustment to Health Net's debt. • Additional stock compensation expense related to the amortization of the fair value increase to Health Net rollover stock awards. • Increased tax expense due to the assumption that Centene would be subject to the IRS Regulation 162(m)(6) beginning in 2015. • Elimination of acquisition related costs. Restructuring Related Charges In connection with the Health Net acquisition, the Company undertook a restructuring plan as a result of the integration of Health Net's operations into its business, resulting in a reduction in workforce beginning in 2016 and expected to continue through early 2017. The restructuring related costs are classified as SG&A expenses in the Consolidated Statements of Operations. Changes in the restructuring liability for the year ended December 31, 2016 were as follows ($ in millions): December 31, 2016 Employee Termination Costs Stock Based Compensation Total Total accrued restructuring costs as of December 31, 2015 $ — $ — $ — Charges incurred 46 43 89 Paid/settled (28 ) (43 ) (71 ) Total accrued restructuring costs as of December 31, 2016 $ 18 $ — $ 18 For the year ended December 31, 2016 , the Company recorded employee termination costs of $46 million and stock based compensation of $43 million in the Managed Care Segment. The Company expects to record a total of approximately $51 million of employee termination costs and $45 million of stock based compensation in connection with the acquisition, the majority of which was expensed in 2016. The remainder is to be incurred in early 2017. Commitments In connection with obtaining regulatory approval of the Health Net acquisition from the California Department of Insurance and th e California Department of Managed Health Care, the Company committed to certain undertakings (the Undertakings). The Undertakings included, among other items, operational commitments around premiums, dividend restrictions, minimum Risk Based Capital (RBC) levels, local offices, growth, accreditation, HEDIS scores and other quality measures, network adequacy, certifications, investments and capital expenditures. Specifically, the Company agreed to, among other things: • invest an additional $30 million through the California Organized Investment Network over the five years following completion of the acquisition; • build a service center in an economically distressed community in California, investing $200 million over 10 years and employing at least 300 people; • contribute $65 million to improve enrollee health outcomes ( $10 million over 10 years), support locally based consumer assistance programs ( $5 million over five years) and strengthen the health care delivery system ( $50 million over five years), (of which, the present value of $61 million was expensed in the year ended December 31, 2016 , and classified as SG&A expenses in the Consolidated Statements of Operations); and • invest $75 million of its investment portfolio in vehicles supporting California’s health care infrastructure.

Acquisitions and Noncontrolling

Acquisitions and Noncontrolling Interest	12 Months Ended
	Dec. 31, 2016
Business Combinations [Abstract]
Acquisitions and Noncontrolling Interest	Acquisitions and Noncontrolling Interest Acquisitions Health Net. On March 24, 2016, the Company acquired all of the issued and outstanding shares of Health Net, a publicly traded managed care organization that delivers health care services through health plans and government-sponsored managed care plans. See Note 3, Health Net, for further discussion on the acquisition. Agate Resources, Inc. In September 2015, the Company completed the acquisition of Agate Resources, Inc. (Agate) for $114 million . Agate is a diversified holding company that offers primarily Medicaid and other healthcare products and services to Oregon residents. The fair value of consideration of $114 million consists of initial cash consideration of $93 million , the present value of future cash payments of $12 million to be paid out over a three year period, and the fair value of estimated contingent consideration of $9 million . A portion of the contingent consideration is based on the achievement of underwriting targets and is being paid in cash over a three year period; the remainder is based on the net proceeds of a retrospective rate adjustment, which was settled in 2016. The Company's allocation of fair value resulted in goodwill of $42 million and other identifiable intangible assets of $39 million . The goodwill is not deductible for income tax purposes. The acquisition is recorded in the Managed Care segment. Noncontrolling Interest The Company has consolidated subsidiaries where it maintains less than 100% ownership. The Company’s ownership interest for each subsidiary as of December 31, are as follows: 2016 2015 2014 Celtic Insurance Company 100 % 75 % 100 % Cenpatico Integrated Care 80 % 80 % 80 % Centurion 51 % 51 % 51 % Home State Health Plan 95 % 95 % 95 % The Practice (Group) Limited (TPG) (1) 75 % 49 % 49 % U.S. Medical Management 68 % 68 % 68 % (1) In 2016, the Company purchased a controlling interest in TPG for $8 million . Net income attributable to Centene Corporation and transfers from (to) noncontrolling interest entities are as follows ($ in millions): Year Ended December 31, 2016 2015 2014 Net earnings attributable to Centene Corporation $ 559 $ 356 $ 268 Transfers from (to) the noncontrolling interest: Increase in equity for distributions from and consolidation of noncontrolling interest 2 11 — Reclassification to redeemable noncontrolling interest — 1 (9 ) Net transfers from (to) noncontrolling interest 2 12 (9 ) Changes from net earnings attributable to Centene Corporation and net transfers from (to) the noncontrolling interest $ 561 $ 368 $ 259 Redeemable Noncontrolling Interest As a result of put option agreements, noncontrolling interest is considered redeemable and is classified in the Redeemable Noncontrolling Interest section of the Consolidated Balance Sheets. Noncontrolling interest is initially measured at fair value using the binomial lattice model as of the acquisition date. The Company has elected to accrete changes in the redemption value through additional paid-in capital over the period from the date of issuance to the earliest redemption date following the effective interest method. A reconciliation of the changes in the Redeemable Noncontrolling Interest is as follows ($ in millions): Balance, December 31, 2015 $ 156 Noncontrolling interest related to TPG acquisition 3 Noncontrolling interest repurchased related to Celtic Insurance Company (12 ) Net losses attributable to noncontrolling interest (2 ) Balance, December 31, 2016 $ 145 Pro forma disclosures related to the acquisitions other than Health Net (see Note 3, Health Net ) have been excluded as they were deemed to be immaterial.

Short-Term And Long-Term Invest

Short-Term And Long-Term Investments, Restricted Deposits	12 Months Ended
	Dec. 31, 2016
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): December 31, 2016 December 31, 2015 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 364 $ — $ (1 ) $ 363 $ 431 $ — $ (2 ) $ 429 Corporate securities 1,933 12 (13 ) 1,932 859 2 (8 ) 853 Restricted certificates of deposit 5 — — 5 5 — — 5 Restricted cash equivalents 6 — — 6 78 — — 78 Municipal securities 1,767 1 (35 ) 1,733 496 2 (1 ) 497 Asset backed securities 317 1 (1 ) 317 163 — (1 ) 162 Residential mortgage backed securities 219 1 (5 ) 215 66 1 — 67 Commercial mortgage backed securities 343 — (5 ) 338 40 — — 40 Cost and equity method investments 163 — — 163 71 — — 71 Life insurance contracts 116 — — 116 16 — — 16 Total $ 5,233 $ 15 $ (60 ) $ 5,188 $ 2,225 $ 5 $ (12 ) $ 2,218 The Company’s investments are classified as available-for-sale with the exception of life insurance contracts and certain cost and equity method investments. 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 December 31, 2016 , 95% of the Company’s investments in rated securities carry an investment grade rating by S&P and Moody’s. At December 31, 2016 , the Company held certificates of deposit, life insurance contracts and cost and equity method investments which did not carry a credit rating. 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 3.7 years at December 31, 2016. In January 2016, the Company completed a 19% investment in a data analytics business, and as a result, issued the selling stockholders 1.1 million shares of Centene common stock, valued at $68 million . The investment is being accounted for using the equity method of accounting due to the Company's significant influence of the business. The fair value of available-for-sale investments with gross unrealized losses by investment type and length of time that individual securities have been in a continuous unrealized loss position were as follows ($ in millions): December 31, 2016 December 31, 2015 Less Than 12 Months 12 Months or More Less Than 12 Months 12 Months or More Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value U.S. Treasury securities and obligations of U.S. government corporations and agencies $ (1 ) $ 215 $ — $ 2 $ (2 ) $ 294 $ — $ 14 Corporate securities (12 ) 1,020 (1 ) 39 (6 ) 561 (2 ) 41 Municipal securities (35 ) 1,423 — 30 (1 ) 208 — 5 Asset backed securities (1 ) 101 — 18 (1 ) 121 — 8 Residential mortgage backed securities (5 ) 188 — — — 30 — — Commercial mortgage backed securities (5 ) 271 — — — 34 — — Total $ (59 ) $ 3,218 $ (1 ) $ 89 $ (10 ) $ 1,248 $ (2 ) $ 68 As of December 31, 2016 , the gross unrealized losses were generated from 1,881 positions out of a total of 2,845 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 other-than-temporary and 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, there is no indication of other-than-temporary impairment for these securities. During the years ended December 31, 2016 , 2015 and 2014, the company recognized $5 million , $8 million and $6 million , respectively, of income from equity method investments. The contractual maturities of short term and long term investments and restricted deposits are as follows ($ in millions): December 31, 2016 December 31, 2015 Investments Restricted Deposits Investments Restricted Deposits Amortized Cost Fair Value Amortized Cost Fair Value Amortized Cost Fair Value Amortized Cost Fair Value One year or less $ 500 $ 500 $ 91 $ 91 $ 176 $ 176 $ 93 $ 93 One year through five years 1,982 1,974 47 47 1,662 1,654 22 22 Five years through ten years 1,101 1,089 — — 267 268 — — Greater than ten years 633 617 — — 5 5 — — Asset-backed securities 879 870 — — — — — — Total $ 5,095 $ 5,050 $ 138 $ 138 $ 2,110 $ 2,103 $ 115 $ 115 Actual maturities may differ from contractual maturities due to call or prepayment options. Cost and equity method investments and life insurance contracts are included in the five years through ten years category. 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. The Company continuously monitors investments for other-than-temporary impairment. 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 impairment loss for cost and equity method investments when evidence demonstrates that it is other-than-temporarily impaired. Evidence of a loss in value that is other-than-temporary may include the absence of an ability to recover the carrying amount of the investment or the inability of the investee to sustain a level of earnings that would justify the carrying amount of the investment.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2016
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 December 31, 2016 , 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 $ 3,930 $ — $ — $ 3,930 Investments available for sale: U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 221 $ 15 $ — $ 236 Corporate securities — 1,932 — 1,932 Municipal securities — 1,733 — 1,733 Asset backed securities — 317 — 317 Residential mortgage backed securities — 215 — 215 Commercial mortgage backed securities — 338 — 338 Total investments $ 221 $ 4,550 $ — $ 4,771 Restricted deposits available for sale: Cash and cash equivalents $ 6 $ — $ — $ 6 Certificates of deposit 5 — — 5 U.S. Treasury securities and obligations of U.S. government corporations and agencies 127 — — 127 Total restricted deposits $ 138 $ — $ — $ 138 Other long term assets: Interest rate swap agreements $ — $ 4 $ — $ 4 Total assets at fair value $ 4,289 $ 4,554 $ — $ 8,843 Liabilities Other long term liabilities: Interest rate swap agreements $ — $ 62 $ — $ 62 Total liabilities at fair value $ — $ 62 $ — $ 62 The following table summarizes fair value measurements by level at December 31, 2015 , 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 $ 1,760 $ — $ — $ 1,760 Investments available for sale: U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 325 $ 72 $ — $ 397 Corporate securities — 853 — 853 Municipal securities — 497 — 497 Asset backed securities — 162 — 162 Residential mortgage backed securities — 67 — 67 Commercial mortgage backed securities — 40 — 40 Total investments $ 325 $ 1,691 $ — $ 2,016 Restricted deposits available for sale: Cash and cash equivalents $ 78 $ — $ — $ 78 Certificates of deposit 5 — — 5 U.S. Treasury securities and obligations of U.S. government corporations and agencies 32 — — 32 Total restricted deposits $ 115 $ — $ — $ 115 Other long term assets: Interest rate swap agreements $ — $ 11 $ — $ 11 Total assets at fair value $ 2,200 $ 1,702 $ — $ 3,902 Liabilities Other long term liabilities: Interest rate swap agreements $ — $ 2 $ — $ 2 Total liabilities at fair value $ — $ 2 $ — $ 2 The Company periodically transfers U.S. Treasury securities and obligations of U.S. government corporations and agencies between Level I and Level II fair value measurements dependent upon the level of trading activity for the specific securities at the measurement date. The Company’s policy regarding the timing of transfers between Level I and Level II is to measure and record the transfers at the end of the reporting period. At December 31, 2016 , there were $1 million of transfers from Level I to Level II and $45 million of transfers from Level II to Level I. 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. The aggregate carrying amount of the Company’s life insurance contracts and other non-majority owned investments, which approximates fair value, was $279 million and $87 million as of December 31, 2016 and December 31, 2015 , respectively.

Property, Software And Equipmen

Property, Software And Equipment	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Property, Software and Equipment	Property, Software and Equipment Property, software and equipment consist of the following as of December 31 ($ in millions): 2016 2015 Land $ 113 $ 104 Building 271 223 Computer software 377 237 Computer hardware 179 105 Furniture and office equipment 126 92 Leasehold improvements 173 108 1,239 869 Less accumulated depreciation (442 ) (351 ) Property, software and equipment, net $ 797 $ 518 As of December 31, 2016 and 2015 , the Company had assets acquired under capital leases included above of $5 million and $6 million , net of accumulated amortization of $4 million and $4 million , respectively. Amortization on assets under capital leases charged to expense is included in depreciation expense. Depreciation expense for the years ended December 31, 2016, 2015 and 2014 was $101 million , $78 million and $65 million , respectively.

Goodwill And Intangible Assets

Goodwill And Intangible Assets	12 Months Ended
	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	Goodwill and Intangible Assets The following table summarizes the changes in goodwill by operating segment ($ in millions): Managed Care Specialty Services Total Balance as of December 31, 2014 $ 276 $ 478 $ 754 Acquisitions and purchase accounting adjustments 103 3 106 Impairment (18 ) — (18 ) Balance as of December 31, 2015 361 481 842 Acquisitions and purchase accounting adjustments 3,331 542 3,873 Translation impact (3 ) — (3 ) Balance as of December 31, 2016 $ 3,689 $ 1,023 $ 4,712 Goodwill was related to the acquisitions and finalization of fair value allocations discussed in Note 3 , Health Net and Note 4 , Acquisitions and Noncontrolling Interest . Intangible assets at December 31, consist of the following ($ in millions): Weighted Average Life in Years 2016 2015 2016 2015 Purchased contract rights $ 1,171 $ 71 12.6 8.8 Provider contracts 285 103 10.7 11.1 Customer relationships 22 26 8.2 8.1 Trade names 163 12 9.6 7.3 Developed technology 110 5 5.0 5.0 Intangible assets 1,751 217 11.5 9.8 Less accumulated amortization: Purchased contract rights (95 ) (21 ) Provider contracts (55 ) (24 ) Customer relationships (21 ) (14 ) Trade names (17 ) (2 ) Developed technology (18 ) (1 ) Total accumulated amortization (206 ) (62 ) Intangible assets, net $ 1,545 $ 155 Amortization expense was $147 million , $24 million and $16 million for the years ended December 31, 2016, 2015 and 2014 , respectively. Estimated total amortization expense related to intangible assets for each of the five succeeding fiscal years is as follows ($ in millions): Year Expense 2017 $ 155 2018 152 2019 152 2020 150 2021 133

Medical Claims Liability

Medical Claims Liability	12 Months Ended
	Dec. 31, 2016
Liability for Unpaid Claims and Claims Adjustment Expense, Activity in Liability [Abstract]
Medical Claims Liability	Medical Claims Liability The following table summarizes the change in medical claims liability by operating segment ($ in millions): Managed Care Specialty Services Consolidated Total Balance, January 1, 2014, net $ 1,101 $ 11 $ 1,112 Incurred related to: Current year 12,468 352 12,820 Prior years (141 ) (1 ) (142 ) Total incurred 12,327 351 12,678 Paid related to: Current year 10,796 326 11,122 Prior years 936 9 945 Total paid 11,732 335 12,067 Balance, December 31, 2014, net $ 1,696 $ 27 $ 1,723 Acquisitions 79 — 79 Incurred related to: Current year 16,974 497 17,471 Prior years (223 ) (6 ) (229 ) Total incurred 16,751 491 17,242 Paid related to: Current year 14,826 453 15,279 Prior years 1,448 19 1,467 Total paid 16,274 472 16,746 Balance at December 31, 2015, net $ 2,252 $ 46 $ 2,298 Acquisitions 1,482 — 1,482 Incurred related to: Current year 30,073 873 30,946 Prior years (303 ) (7 ) (310 ) Total incurred 29,770 866 30,636 Paid related to: Current year 27,714 818 28,532 Prior years 1,921 39 1,960 Total paid 29,635 857 30,492 Balance at December 31, 2016, net $ 3,869 $ 55 $ 3,924 Reinsurance recoverable 5 — 5 Balance, December 31, 2016 $ 3,874 $ 55 $ 3,929 Reinsurance recoverables related to medical claims are included in premium and related 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 HBR and other return of premium programs, approximately $39 million , $47 million , and $26 million of the “Incurred related to: Prior years” was recorded as a reduction to premium revenues in 2016, 2015 and 2014, respectively. Further, claims processing initiatives yielded increased claim payment recoveries and coordination of benefits related to prior year dates of service. Changes in medical utilization and cost trends and the effect of medical management initiatives may also contribute to changes in medical claim liability estimates. While the Company has evidence that medical management initiatives are effective on a case by case basis, medical management initiatives primarily focus on events and behaviors prior to the incurrence of the medical event and generation of a claim. Accordingly, any change in behavior, leveling of care, or coordination of treatment occurs prior to claim generation and as a result, the costs prior to the medical management initiative are not known by the Company. Additionally, certain medical management initiatives are focused on member and provider education with the intent of influencing behavior to appropriately align the medical services provided with the member's acuity. In these cases, determining whether the medical management initiative changed the behavior cannot be determined. Because of the complexity of its business, the number of states in which it operates, and the volume of claims that it processes, the Company is unable to practically quantify the impact of these initiatives on its changes in estimates of IBNR. The Company periodically reviews actual and anticipated experience compared to the assumptions used to establish medical costs. The Company establishes premium deficiency reserves if actual and anticipated experience indicates that existing policy liabilities together with the present value of future gross premiums will not be sufficient to cover the present value of future benefits, settlement and maintenance costs. Information about incurred and paid claims development as of December 31, 2016 is included in the table below and is inclusive of claims incurred and paid related to the Health Net business prior and subsequent to the acquisition date. The claims development information for all periods preceding the most recent reporting period is considered required supplementary information. Incurred and paid claims development as of December 31, 2016 is as follows ($ in millions) : Cumulative Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, Claim Year 2014 (unaudited) 2015 (unaudited) 2016 Managed Care: 2014 $ 23,790 $ 23,472 $ 23,468 2015 30,122 29,833 2016 33,782 Total incurred claims $ 87,083 Specialty Services: 2014 $ 352 $ 348 $ 346 2015 497 492 2016 873 Total incurred claims $ 1,711 Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, Claim Year 2014 (unaudited) 2015 (unaudited) 2016 Managed Care: 2014 $ 20,415 $ 22,895 $ 23,450 2015 27,211 29,539 2016 30,225 Total payment of incurred claims $ 83,214 Managed Care medical claims liability $ 3,869 Specialty Services: 2014 $ 326 $ 346 $ 346 2015 453 492 2016 818 Total payment of incurred claims $ 1,656 Specialty Services medical claims liability $ 55 Consolidated total, net of reinsurance $ 3,924 Incurred claims and allocated claim adjustment expenses, net of reinsurance, IBNR plus expected development on reported claims and cumulative claims data as of December 31, 2016 are included in the following table and are inclusive of the acquired Health Net business. For claims frequency information summarized below, a claim is defined as the financial settlement of a single medical event in which remuneration was paid to the servicing provider. 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. We estimate our 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. Information is summarized as follows (in millions): December 31, 2016 Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance Total IBNR Plus Expected Development on Reported Claims Cumulative Paid Claims Managed Care: 2014 $ 23,468 $ 2 121.0 2015 29,833 52 153.4 2016 33,782 3,001 164.9 Specialty Services: 2014 $ 346 $ — 2.7 2015 492 — 3.1 2016 873 49 6.3

Affordable Care Act

Affordable Care Act	12 Months Ended
	Dec. 31, 2016
Affordable Care Act [Abstract]
Affordable Care Act	Affordable Care Act The Affordable Care Act (ACA) established risk spreading premium stabilization programs effective January 1, 2014. These programs, commonly referred to as the “three Rs,” include a permanent risk adjustment program, a transitional reinsurance program, and a temporary risk corridor program. Additionally, the ACA established a minimum annual MLR and cost sharing reductions. Each of the three R programs are taken into consideration to determine if the Company’s estimated annual medical costs are less than the minimum loss ratio and require an adjustment to Premium revenue to meet the minimum MLR. During 2016, the Company recognized a $51 million net pre-tax benefit related to the reconciliation of 2015 risk adjustment and reinsurance programs. The Company's receivables (payables) for each of these programs are as follows at each year ended ($ in millions): December 31, 2016 December 31, 2015 Risk adjustment $ (425 ) $ (108 ) Reinsurance 122 24 Risk corridor (3 ) (4 ) Minimum MLR (18 ) (15 ) Cost sharing reductions (147 ) (40 )

Debt

Debt	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Debt	Debt Debt consists of the following ($ in millions): December 31, 2016 December 31, 2015 $425 million 5.75% Senior notes, due June 1, 2017 $ — $ 428 $1,400 million 5.625% Senior notes, due February 15, 2021 1,400 — $1,000 million 4.75% Senior notes, due May 15, 2022 1,008 500 $1,000 million 6.125% Senior notes, due February 15, 2024 1,000 — $1,200 million 4.75% Senior notes, due January 15, 2025 1,200 — Fair value of interest rate swap agreements (58 ) 9 Senior notes 4,550 937 Revolving credit agreement 100 225 Mortgage notes payable 64 67 Capital leases and other 18 6 Debt issuance costs (77 ) (14 ) Total debt 4,655 1,221 Less current portion (4 ) (5 ) Long term debt $ 4,651 $ 1,216 Senior Notes In December 2016, the Company redeemed the outstanding principal balance on the $400 million 6.375% Senior Notes, due June 1, 2017 , plus applicable premium for early redemption and accrued and unpaid interest to the redemption date, for cash totaling $411 million . The Company recognized a loss on extinguishment of debt of $3 million on the redemption of these notes. In November 2016, the Company redeemed the outstanding principal balance on the $425 million 5.75% Senior Notes due June 1, 2017 , plus applicable premium for early redemption and accrued and unpaid interest to the redemption date, for cash totaling $447 million . The Company recognized a loss on extinguishment of debt of $10 million on the redemption of these notes. The Company also recognized a gain of $2 million on the termination of the $250 million interest rate swap agreement associated with these notes. In November 2016, the Company issued $1,200 million in aggregate principal amount of 4.75% Senior Notes due 2025 ( $1,200 million Notes). The Company used the net proceeds of the offering to redeem its 5.75% Senior Notes due 2017 and Health Net Inc.'s 6.375% Senior Notes due 2017, to repay amounts outstanding under its Revolving Credit Facility, to pay related fees and expenses and for general corporate purposes. In June 2016, the Company issued an additional $500 million in aggregate principal amount of 4.75% Senior Notes due 2022 ( $500 Million Add-on Notes) at a premium to yield of 4.41% . The $500 Million Add-on Notes were offered as additional debt securities under the indenture governing the $ 500 million in aggregate principal amount of 4.75% Senior Notes issued in April 2014. The Company used the net proceeds of the offering to repay amounts outstanding under its Revolving Credit Facility and to pay offering related fees and expenses. In February 2016, a wholly owned unrestricted subsidiary of the Company (Escrow Issuer) issued $1,400 million in aggregate principal amount of 5.625% Senior Notes ( $1,400 Million Notes) at par due 2021 and $1,000 million in aggregate principal amount of 6.125% Senior Notes ( $1,000 Million Notes) at par due 2024. In July 2016, the Company completed an exchange offer, whereby it offered to exchange all of the outstanding $1,400 Million Notes and the $1,000 Million Notes for identical securities that have been registered under the Securities Act of 1933. The Company used the net proceeds of the offering, together with borrowings under the Company's new $1,000 million revolving credit facility and cash on hand, primarily to fund the cash consideration for the Health Net acquisition, and to pay acquisition and offering related fees and expenses. In connection with the February 2016 issuance, the Company entered into interest rate swap agreements for notional amounts of $600 million and $1,000 million, at floating rates of interest based on the three month LIBOR plus 4.22% and the three month LIBOR plus 4.44% , respectively. Gains and losses due to changes in the fair value of the interest rate swaps completely offset changes in the fair value of the hedged portion of the underlying debt and are recorded as an adjustment to the $1,400 Million Notes and $1,000 Million Notes. In connection with the closing of the Health Net acquisition, the Company assumed the $400 million in aggregate principal amount of Health Net's 6.375% Senior Notes due 2017, recorded at acquisition date fair value of $418 million. These Senior Notes were redeemed in December 2016. In January 2015, the Company issued an additional $200 million of 4.75% Senior Notes ( $200 Million Add-on Notes) at par. The $200 Million Add-on Notes were offered as additional debt securities under the indenture governing the $300 million of 4.75% Senior Notes issued in April 2014. In connection with the January 2015 issuance, the Company entered into interest rate swap agreements for a notional amount of $200 million at a floating rate of interest based on the three month LIBOR plus 2.88% . Gains and losses due to changes in the fair value of the interest rate swap completely offset changes in the fair value of the hedged portion of the underlying debt and are recorded as an adjustment to the $200 Million Add-on Notes. The indentures governing the $1,400 Million Notes, the $1,000 million of 4.75% Senior Notes due 2022, the $1,000 Million Notes and the $1,200 Million Notes contain non-financial and financial covenants of Centene Corporation, including requirements of a minimum fixed charge coverage ratio. At December 31, 2016 , the Company was in compliance with all covenants. Interest Rate Swaps The Company uses interest rate swap agreements to convert a portion of its interest rate exposure from fixed rates to floating rates to more closely align interest expense with interest income received on its cash equivalent and variable rate investment balances. The Company has $2,100 million of notional amount of interest rate swap agreements consisting of: • $600 million expiring on February 15, 2021; • $500 million expiring on May 15, 2022; and, • $1,000 million expiring on February 15, 2024. Under the Swap Agreements, the Company receives a fixed rate of interest and pays an average variable rate of the three month LIBOR plus 3.92% adjusted quarterly. At December 31, 2016, the weighted average rate was 4.83% . The Swap Agreements are formally designated and qualify as fair value hedges and are recorded at fair value in the Consolidated Balance Sheets in other assets and/or other liabilities. Gains and losses due to changes in fair value of the interest rate swap agreements completely offset changes in the fair value of the hedged portion of the underlying debt. Therefore, no gain or loss has been recognized due to hedge ineffectiveness. Offsetting changes in fair value of both the interest rate swaps and the hedged portion of the underlying debt both were recognized in interest expense in the Consolidated Statement of Operations. The Company does not hold or issue any derivative instrument for trading or speculative purposes. The fair values of the Swap Agreements as of December 31, 2016 were assets of $4 million and liabilities of $62 million , and are included in other long term assets and other long term liabilities, respectively in the Consolidated Balance Sheet. The fair value of the Swap Agreements as of December 31, 2015 were assets of $11 million and liabilities of $2 million , and are included in other long term assets and other long term liabilities, respectively in the Consolidated Balance Sheet. The fair value of the Swap Agreements excludes accrued interest and takes into consideration current interest rates and current likelihood of the swap counterparties' compliance with its contractual obligations. Revolving Credit Agreement In connection with the closing of the Health Net acquisition in March 2016, the Company's existing unsecured $500 million revolving credit facility was terminated and simultaneously replaced with a new $1,000 million unsecured revolving credit facility. Borrowings under the agreement bear interest based upon LIBOR rates, the Federal Funds Rate or the Prime Rate. The agreement has a maturity date of March 24, 2021 . As of December 31, 2016 , the Company had $100 million of borrowings outstanding under the agreement with a weighted average interest rate of 4.5% , and the Company was in compliance with all covenants. The revolving credit facility contains both non-financial and financial covenants, including requirements of minimum fixed charge coverage ratios and maximum debt-to-EBITDA ratios. The Company is required to not exceed a maximum debt-to-EBITDA ratio of 3.5 to 1.0 prior to December 31, 2016 and 3.0 to 1.0 on and subsequent to December 31, 2016. As of December 31, 2016 , there were no limitations on the availability under the revolving credit agreement as a result of the debt-to-EBITDA ratio. Also, upon the closing of the Health Net acquisition, the Company assumed, fully repaid $285 million in outstanding borrowings under, and terminated the existing Health Net revolving credit facility. Mortgage Notes Payable The Company has a non-recourse mortgage note of $64 million at December 31, 2016 collateralized by its corporate headquarters building. The mortgage note is due January 1, 2021 and bears a 5.14% interest rate. The collateralized property had a net book value of $173 million at December 31, 2016 . Letters of Credit & Surety Bonds The Company had outstanding letters of credit of $71 million as of December 31, 2016, which were not part of the revolving credit facility. The Company also had letters of credit for $45 million (valued at December 31, 2016 conversion rate), or €42 million , representing its proportional share of the letters of credit issued to support Ribera Salud's outstanding debt, which are a part of the revolving credit facility. Collectively, the letters of credit bore interest at 1.42% as of December 31, 2016. The Company had outstanding surety bonds of $365 million as of December 31, 2016. Aggregate maturities for the Company's debt are as follows ($ in millions): 2017 $ 4 2018 4 2019 16 2020 4 2021 1,404 Thereafter 3,350 Total $ 4,782 The fair value of outstanding debt was approximately $4,676 million and $1,239 million at December 31, 2016 and 2015 , respectively.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2016
Stockholders' Equity Note [Abstract]
Stockholders' Equity	Stockholders' Equity The Company has 10,000,000 authorized shares of preferred stock at $.001 par value. At December 31, 2016 , there were no preferred shares outstanding. The Company's Board of Directors has authorized a stock repurchase program for up to 8,000,000 shares of the Company's common stock from time to time on the open market or through privately negotiated transactions. No duration has been placed on the repurchase program. The Company has 3,335,448 available shares remaining under the program for repurchases as of December 31, 2016 . The Company reserves the right to discontinue the repurchase program at any time. During the year ended December 31, 2016 , the Company did not repurchase any shares through this publicly announced program. As a component of the employee stock compensation plan, employees can use shares of stock which have vested to satisfy statutory tax withholding obligations. As part of this plan, the Company repurchased 1,078,335 shares at an aggregate cost of $63 million in 2016 and 918,628 shares at an aggregate cost of $53 million in 2015. These shares are included in the Company's treasury stock. In March 2016, the Company issued 48,449,444 shares of Centene stock, with a fair value of approximately $3,038 million . In January 2016, the Company completed a 19% investment in a data analytics business and issued 1,144,462 shares of Centene common stock to the selling stockholders. The investment is being accounted for using the equity method of accounting, due to the Company's significant influence on the business.

Statutory Capital Requirements

Statutory Capital Requirements And Dividend Restrictions	12 Months Ended
	Dec. 31, 2016
Statutory Capital Requirements And Dividend Restrictions [Abstract]
Statutory Capital Requirements and Dividend Restriction	Statutory Capital Requirements and Dividend Restrictions Various state laws require Centene's regulated subsidiaries to maintain minimum capital levels specified by each state and restrict the amount of dividends that may be paid without prior regulatory approval. At December 31, 2016 and 2015 , Centene's subsidiaries, including Kentucky Spirit, had aggregate statutory capital and surplus of $4,529 million and $2,284 million , respectively, compared with the required minimum aggregate statutory capital and surplus of $2,259 million and $1,195 million , respectively. As of December 31, 2016, the amount of capital and surplus or net worth that was unavailable for the payment of dividends or return of capital to the Company was $2,259 million in the aggregate.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The consolidated income tax expense consists of the following for the years ended December 31 ($ in millions): 2016 2015 2014 Current provision Federal $ 485 $ 332 $ 225 State and local 22 26 13 Total current provision 507 358 238 Deferred provision 92 (19 ) (42 ) Total income tax expense $ 599 $ 339 $ 196 The reconciliation of the tax provision at the U.S. federal statutory rate to income tax expense for the years ended December 31 is as follows ($ in millions): 2016 2015 2014 Earnings from continuing operations, before income tax expense $ 1,157 $ 697 $ 457 (Earnings) loss attributable to flow through noncontrolling interest (8 ) 1 4 Earnings from continuing operations, less noncontrolling interest, before income tax expense 1,149 698 461 Tax provision at the U.S. federal statutory rate 402 244 162 State income taxes, net of federal income tax benefit 10 15 6 Nondeductible compensation 23 2 (13 ) ACA Health Insurer Fee 162 75 44 Other, net 2 3 (3 ) Income tax expense $ 599 $ 339 $ 196 The tax effects of temporary differences which give rise to deferred tax assets and liabilities are presented below for the years ended December 31 ($ in millions): 2016 2015 Deferred tax assets: Medical claims liability $ 66 $ 27 Nondeductible liabilities 39 14 Net operating loss and tax credit carryforwards 101 22 Compensation accruals 156 73 Acquisition costs — 10 Premium and related receivables 79 36 Other 14 9 Deferred tax assets 455 191 Valuation allowance (86 ) (11 ) Net deferred tax assets $ 369 $ 180 Deferred tax liabilities: Intangible assets $ 577 $ 46 Prepaid assets 17 8 Fixed assets and intangibles 65 31 Investments in joint ventures 11 6 Other 2 2 Deferred tax liabilities 672 93 Net deferred tax assets (liabilities) $ (303 ) $ 87 Valuation allowances are provided when it is considered more likely than not that deferred tax assets will not be realized. The valuation allowances primarily relate to future tax benefits on certain federal, state and foreign net operating loss and tax credit carryforwards. The $75 million increase in valuation allowance primarily relate s to acquired federal and state net operating loss carryforwards from the Health Net transaction. Federal net operating loss carryforwards of $59 million expire beginning in 2020 through 2036 ; state net operating loss and tax credit carryforwards of $37 million expire beginning in 2017 through 2036 . Substantially all of the non-U.S. tax loss carryforwards have indefinite carryforward periods. The Company maintains a reserve for uncertain tax positions that may be challenged by a tax authority. A rollforward of the beginning and ending amount of uncertain tax positions, exclusive of related interest and penalties, is as follows: Year Ended December 31, 2016 2015 Gross unrecognized tax benefits, beginning of period $ 5 $ 4 Gross increases: Current year tax positions 6 1 Acquired reserves 93 — Gross decreases: Prior year tax positions (1 ) — Statute of limitation lapses (1 ) — Gross unrecognized tax benefits, end of period $ 102 $ 5 Uncertain tax positions increased $93 million due to the acquisition of Health Net. As of December 31, 2016, $87 million of unrecognized tax benefits could impact our effective tax rate in future periods, if recognized. The Company believes it is reasonably possible that its liability for unrecognized tax benefits will decrease in the next twelve months by $5 million as a result of audit settlements and the expiration of statutes of limitations in certain major jurisdictions. The table above excludes interest, net of related tax benefits, which is treated as income tax expense (benefit) under our accounting policy. For the year ended December 31, 2016, the Company recognized net interest expense and penalties related to uncertain positions of $1 million . The Company had $5 million and $1 million of accrued interest and penalties for uncertain tax positions as of December 31, 2016 and 2015, respectively. The company files tax returns for federal as well as numerous state tax jurisdictions. As of December 31, 2016, Health Net is under federal examination for tax years 2011 through 2013. Additionally, tax years subject to federal examination for both Centene and Health Net are 2014 through 2016. In September 2014, the Internal Revenue Service issued final regulations related to the compensation deduction limitation applicable to certain health insurance issuers. The new regulations provided additional information regarding the definition of a health insurance issuer. As a result of this change in regulation, tax benefits of $14 million related to 2013 were recorded during the 2014 period. The Company finalized the 2013 federal audit in the third quarter of 2016 and sustained its compensation deduction limitation position. As of December 31, 2016 and 2015, the Company had $12 million and $8 million , respectively, of undistributed earnings from non-U.S. subsidiaries that are intended to be reinvested in non-U.S. operations. Because these earnings are considered permanently reinvested, no U.S. tax provision has been accrued related to the repatriation of these earnings. The amount of U.S. tax that would be payable on the eventual remittance of such earnings is not material to the Company’s financial statements.

Stock Incentive Plans

Stock Incentive Plans	12 Months Ended
	Dec. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock Incentive Plans	Stock Incentive Plans The Company's stock incentive plans allow for the granting of restricted stock or restricted stock unit awards and options to purchase common stock. Both incentive stock options and nonqualified stock options can be awarded under the plans. No option will be exercisable for longer than ten years after the date of grant. The plans have 6,224,268 shares available for future awards. However, 5,376,101 are legacy Health Net shares and based on the terms of the Health Net acquisition, these shares are only available for awards to legacy Health Net employees and new Centene employees. Compensation expense for stock options and restricted stock unit awards is recognized on a straight-line basis over the vesting period, generally three to five years for stock options and one to 10 years for restricted stock or restricted stock unit awards. Certain restricted stock unit awards contain performance-based as well as service-based provisions. Certain awards provide for accelerated vesting if there is a change in control as defined in the plans. In addition, the Company incorporated retirement provisions in our stock-based compensation agreements beginning in 2016. The total compensation cost that has been charged against income for the stock incentive plans was $148 million , $71 million and $48 million for the years ended December 31, 2016, 2015 and 2014 , respectively. The Company adopted ASU 2016-09 during the fourth quarter of 2016, effective prospectively as of the beginning of the 2016 fiscal year. As a result, excess tax benefits are now recorded in income tax expense in the period in which the exercise or vesting occurs. The total income tax benefit recognized in the income statement for stock-based compensation arrangements was $67 million , $24 million and $17 million for the years ended December 31, 2016, 2015 and 2014 , respectively. In connection with the adoption of the new standard, we have also elected to recognize forfeitures as they occur. Option activity for the year ended December 31, 2016 is summarized below: Shares Weighted Average Exercise Price Aggregate Intrinsic Value ($ in millions) Weighted Average Remaining Contractual Term Outstanding as of December 31, 2015 677,408 $ 11.88 Granted 40,000 59.94 Exercised (397,040 ) 12.25 Forfeited — — Outstanding as of December 31, 2016 320,368 $ 17.44 $ 13 2.9 Exercisable as of December 31, 2016 280,368 $ 11.37 $ 13 1.9 The fair value of each option grant is estimated on the date of the grant using the Black-Scholes option-pricing model with the following weighted-average assumptions: Year Ended December 31, 2016 2015 (1) 2014 (1) Expected life (in years) 4.8 — — Risk-free interest rate 1.6% — — Expected volatility 39.0% — — Expected dividend yield — — — (1) No options were awarded in the years ended December 31, 2015 and 2014. For options granted in the year ended December 31, 2016, the Company used a projected expected life for each award granted based on historical experience of employees' exercise behavior. The expected volatility is primarily based on historical volatility levels. The risk-free interest rates are based on the implied yield currently available on U.S. Treasury instruments with a remaining term equal to the expected life. Other information pertaining to option activity is as follows: Year Ended December 31, 2016 2015 (1) 2014 (1) Weighted-average fair value of options granted $ 59.94 $ — $ — Total intrinsic value of stock options exercised ($ in millions) $ 19 $ 28 $ 17 (1) No options were awarded in the years ended December 31, 2015 and 2014. A summary of the Company's non-vested restricted stock and restricted stock unit shares as of December 31, 2016 , and changes during the year ended December 31, 2016 , is presented below: Shares Weighted Average Grant Date Fair Value Non-vested balance as of December 31, 2015 4,122,003 $ 48.65 Granted 2,120,101 57.71 Converted (1) 1,285,674 62.70 Vested (2,546,543 ) 50.00 Forfeited (190,894 ) 47.65 Non-vested balance as of December 31, 2016 4,790,341 $ 55.75 (1) Health Net awards converted in connection with the acquisition. The total fair value of restricted stock and restricted stock units vested during the years ended December 31, 2016, 2015 and 2014 , was $147 million , $112 million and $82 million , respectively. As of December 31, 2016 , there was $233 million of total unrecognized compensation cost related to non-vested share-based compensation arrangements granted under the plans; that cost is expected to be recognized over a weighted-average period of 2.4 years. The Company maintains an employee stock purchase plan and issued 118,293 shares, 86,819 shares, and 76,088 shares in 2016, 2015 and 2014 , respectively.

Retirement Plan

Retirement Plan	12 Months Ended
	Dec. 31, 2016
Defined Contribution Pension and Other Postretirement Plans Disclosure [Abstract]
Retirement Plan	Retirement Plan Centene has a defined contribution plan which covers substantially all employees who are at least twenty-one years of age. Under the plan, eligible employees may contribute a percentage of their base salary, subject to certain limitations. Centene may elect to match a portion of the employee's contribution. Company expense related to matching contributions to the plan was $37 million , $19 million and $12 million during the years ended December 31, 2016, 2015 and 2014 , respectively.

Commitments

Commitments	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments	Commitments Centene and its subsidiaries lease office facilities and various equipment under non-cancelable operating leases which may contain escalation provisions. The rental expense related to these leases is recorded on a straight-line basis over the lease term, including rent holidays. Tenant improvement allowances are recorded as a liability and amortized against rent expense over the term of the lease. Rent expense was $137 million , $64 million and $46 million for the years ended December 31, 2016, 2015 and 2014 , respectively. Annual non-cancelable minimum lease payments over the next five years and thereafter are as follows ($ in millions): 2017 $ 128 2018 117 2019 105 2020 92 2021 75 Thereafter 114 $ 631 In connection with obtaining regulatory approval of the Health Net acquisition from the California Department of Insurance and the California Department of Managed Health Care, the Company committed to certain undertakings. See Note 3, Health Net for further details.

Contingencies

Contingencies	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Contingencies	Contingencies Overview 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. Kentucky On July 5, 2013, the Company's subsidiary, Kentucky Spirit, terminated its contract with the Commonwealth of Kentucky (the Commonwealth). Kentucky Spirit believed it had a contractual right to terminate the contract and filed a lawsuit in Franklin Circuit Court seeking a declaration of this right. In response, the Commonwealth alleged that Kentucky Spirit's exit constituted a material breach of contract. The Commonwealth sought to recover substantial damages and to enforce its rights under Kentucky Spirit's $25 million performance bond. The Commonwealth asserted that the Commonwealth's expenditures due to Kentucky Spirit's departure range from $28 million to $40 million plus interest, and that the associated CMS expenditures range from $92 million to $134 million . Kentucky Spirit disputed the Commonwealth's alleged damages on several grounds. Prior to terminating the contract, Kentucky Spirit filed a legal complaint in April 2013, amended in October 2014, in Franklin Circuit Court seeking damages against the Commonwealth for losses sustained due to the Commonwealth's alleged breaches. On May 26, 2015, the Commonwealth issued a demand for indemnification to its actuarial firm, for "all defense costs, and any resultant monetary awards in favor of Kentucky Spirit, arising from or related to Kentucky Spirit's claims which are predicated upon the alleged omissions and errors in the Data Book and the certified actuarially sound rates." The actuarial firm moved to intervene in the litigation and the Franklin Circuit Court granted that motion on September 8, 2015. Also, on August 19, 2015, the actuarial firm filed a petition seeking a declaratory judgment that it is not liable to the Commonwealth for indemnification related to the claims asserted by Kentucky Spirit against the Commonwealth. On October 5, 2015, the Commonwealth filed an answer to the actuarial firm's petition and asserted counterclaims/cross-claims against the firm. On November 3, 2016, all parties entered into a settlement agreement with respect to all lawsuits and complaints associated with the aforementioned contract termination. Under the terms of the settlement agreement, Kentucky Spirit received an immaterial cash payment from the Commonwealth's actuarial firm and each party dismissed all claims related to the litigation with prejudice. In addition, the Commonwealth and Kentucky Spirit have agreed that neither party acted in bad faith; that the parties took reasonable positions in light of the applicable contractual language; and that the parties acted in good faith in attempting to address a difficult situation. California The Company's California subsidiary, Health Net of California, Inc. (Health Net California), has been 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, 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 20, 2015 filing of the complaint. This lawsuit is being coordinated with similar lawsuits filed against other entities. The Company expects an initial status conference shortly. The Company intends to vigorously defend itself 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 our financial position and results of operations. Federal Securities Class Action On November 14, 2016, a putative federal securities class action was filed against the Company and certain of its executives in the U.S. District Court for the Central District of California. The plaintiffs in the lawsuit allege that the Company's accounting and related disclosures for certain liabilities acquired in the acquisition of Health Net violated federal securities laws. The Company denies any wrongdoing and is vigorously defending itself against these claims. Nevertheless, this matter is subject to many uncertainties and the Company cannot predict how long this litigation will last or what the ultimate outcome will be, and an adverse outcome in this matter could potentially have a materially adverse impact on our financial position and results of operations. Civil Investigative Demand On December 15, 2016, a Civil Investigative Demand (CID) was issued to Health Net by the United States Department of Justice regarding Health Net’s submission of risk adjustment claims to the CMS under Parts C and D of Medicare. The CID may be related to a federal qui tam lawsuit filed under seal in 2011 naming more than a dozen health insurers including Health Net. The lawsuit was recently unsealed when the Department of Justice intervened in the case with respect to one of the insurers (not Health Net). The Company is complying with the CID and will vigorously defend any lawsuits. 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. Miscellaneous Proceedings Excluding the matters discussed above, the Company is also 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, 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; • litigation arising out of general business activities, such as tax matters, disputes related to health care 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 the miscellaneous 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.

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2016
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 for the years ended December 31 ($ in millions, except per share data): 2016 2015 2014 Earnings (loss) attributable to Centene Corporation: Earnings from continuing operations, net of tax $ 559 $ 356 $ 268 Discontinued operations, net of tax 3 (1 ) 3 Net earnings $ 562 $ 355 $ 271 Shares used in computing per share amounts: Weighted average number of common shares outstanding 159,567,607 119,100,744 116,345,764 Common stock equivalents (as determined by applying the treasury stock method) 4,407,800 3,965,626 4,014,448 Weighted average number of common shares and potential dilutive common shares outstanding 163,975,407 123,066,370 120,360,212 Net earnings (loss) per common share attributable to Centene Corporation: Basic: Continuing operations $ 3.50 $ 2.99 $ 2.30 Discontinued operations 0.02 (0.01 ) 0.03 Basic earnings per common share $ 3.52 $ 2.98 $ 2.33 Diluted: Continuing operations $ 3.41 $ 2.89 $ 2.23 Discontinued operations 0.02 (0.01 ) 0.02 Diluted earnings per common share $ 3.43 $ 2.88 $ 2.25 The calculation of diluted earnings (loss) per common share for 2016, 2015 and 2014 excludes the impact of 126,212 shares, 7,247 shares and 207,980 shares, respectively, related to anti-dilutive stock options, restricted stock and restricted stock units.

Segment Information

Segment Information	12 Months Ended
	Dec. 31, 2016
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. The Managed Care segment also includes the operations previously included in Health Net's Western Region Operations Segment, with the exception of certain operations of its pharmaceutical services and behavioral health subsidiaries. The portions of Health Net's Western Region Operations segment included in the Managed Care segment consist of the following Health Net operations: commercial, Medicare, Medicaid and dual eligible health plans, primarily in Arizona, California, Oregon and Washington. The Specialty Services segment consists of Centene’s specialty companies offering auxiliary healthcare services and products. The Specialty Services segment also includes the operations previously included in the Government Contracts segment of Health Net as well as certain operations of its pharmaceutical services and behavioral health subsidiaries, the latter of which Health Net previously included in its Western Region Operations segment. The Government Contracts business includes the Company's government-sponsored managed care support contract with the DoD under the TRICARE program in the North Region, the MFLC contract with the DoD, and other health care related government contracts, including PC3/Choice with the VA. Segment information as of and for the year ended December 31, 2016 , follows ($ in millions): Managed Care Specialty Services Eliminations Consolidated Total Total revenues from external customers $ 37,523 $ 3,084 $ — $ 40,607 Total revenues internal customers 199 5,953 (6,152 ) — Total revenues 37,722 9,037 (6,152 ) 40,607 Earnings from operations 1,070 190 — 1,260 Total assets 17,962 2,235 — 20,197 Segment information as of and for the year ended December 31, 2015 , follows ($ in millions): Managed Care Specialty Services Eliminations Consolidated Total Total revenues from external customers $ 20,544 $ 2,216 $ — $ 22,760 Total revenues internal customers 100 4,864 (4,964 ) — Total revenues 20,644 7,080 (4,964 ) 22,760 Earnings from operations 513 192 — 705 Total assets 6,202 1,137 — 7,339 Segment information as of and for the year ended December 31, 2014 , follows ($ in millions): Managed Care Specialty Services Eliminations Consolidated Total Total revenues from external customers $ 14,775 $ 1,785 $ — $ 16,560 Total revenues internal customers 60 3,019 (3,079 ) — Total revenues 14,835 4,804 (3,079 ) 16,560 Earnings from operations 353 111 — 464 Total assets 4,706 1,118 — 5,824

Quarterly Selected Financial In

Quarterly Selected Financial Information	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Quarterly Selected Financial Information	Quarterly Selected Financial Information (In millions, except share data) (Unaudited) For the Quarter Ended (1) March 31, 2016 June 30, 2016 September 30, 2016 December 31, 2016 Total revenues $ 6,953 $ 10,897 $ 10,846 $ 11,911 Amounts attributable to Centene Corporation common shareholders: Earnings (loss) from continuing operations, net of income tax expense (15 ) 171 148 255 Discontinued operations, net of income tax expense (benefit) (1 ) (1 ) (1 ) 6 Net earnings (loss) $ (16 ) $ 170 $ 147 $ 261 Net earnings (loss) per common share attributable to Centene Corporation: Basic: Continuing operations $ (0.12 ) $ 1.00 $ 0.87 $ 1.49 Discontinued operations (0.01 ) — (0.01 ) 0.04 Basic earnings per common share $ (0.13 ) $ 1.00 $ 0.86 $ 1.53 Diluted: Continuing operations $ (0.12 ) $ 0.98 $ 0.84 $ 1.45 Discontinued operations (0.01 ) (0.01 ) — 0.04 Diluted earnings per common share $ (0.13 ) $ 0.97 $ 0.84 $ 1.49 Weighted average number of common shares outstanding: Basic 125,543,076 170,558,778 170,774,587 171,143,624 Diluted 125,543,076 174,848,996 175,495,339 175,511,179 (1) The Company early adopted ASU 2016-09 during the fourth quarter of 2016. The ASU requires adjustments be reflected as of the beginning of the fiscal year of adoption and as a result, prior periods have been restated accordingly. Refer to Note 2, Summary of Significant Accounting Policies . For the Quarter Ended March 31, June 30, September 30, December 31, Total revenues $ 5,131 $ 5,506 $ 5,821 $ 6,302 Amounts attributable to Centene Corporation common shareholders: Earnings from continuing operations, net of income tax expense 64 88 92 112 Discontinued operations, net of income tax expense (benefit) (1 ) — 1 (1 ) Net earnings $ 63 $ 88 $ 93 $ 111 Net earnings (loss) per common share attributable to Centene Corporation: Basic: Continuing operations $ 0.54 $ 0.74 $ 0.77 $ 0.94 Discontinued operations (0.01 ) — 0.01 (0.01 ) Basic earnings per common share $ 0.53 $ 0.74 $ 0.78 $ 0.93 Diluted: Continuing operations $ 0.52 $ 0.72 $ 0.75 $ 0.91 Discontinued operations (0.01 ) — 0.01 (0.01 ) Diluted earnings per common share $ 0.51 $ 0.72 $ 0.76 $ 0.90

Condensed Financial Information

Condensed Financial Information Of Registrant	12 Months Ended
	Dec. 31, 2016
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Condensed Financial Information of Registrant	Condensed Financial Information of Registrant Centene Corporation (Parent Company Only) Condensed Balance Sheets (In millions, except share data) December 31, 2016 2015 ASSETS Current assets: Cash and cash equivalents $ 5 $ 4 Short term investments, at fair value (amortized cost $1 and $5, respectively) 1 5 Other current assets 29 25 Total current assets 35 34 Long term investments, at fair value (amortized cost $19 and $6, respectively) 19 6 Investment in subsidiaries 10,674 3,435 Other long term assets 52 35 Total assets $ 10,780 $ 3,510 LIABILITIES AND STOCKHOLDERS' EQUITY Current liabilities $ 78 $ 13 Long term debt 4,573 1,147 Other long term liabilities 75 26 Total liabilities 4,726 1,186 Redeemable noncontrolling interest 145 156 Stockholders' equity: Preferred stock, $.001 par value; authorized 10,000,000 shares; no shares issued or outstanding at December 31, 2016 and December 31, 2015 — — Common stock, $.001 par value; authorized 400,000,000 shares; 178,134,306 issued and 171,919,071 outstanding at December 31, 2016, and 126,855,477 issued and 120,342,981 outstanding at December 31, 2015 — — Additional paid-in capital 4,190 956 Accumulated other comprehensive loss (36 ) (10 ) Retained earnings 1,920 1,358 Treasury stock, at cost (6,215,235 and 6,512,496 shares, respectively) (179 ) (147 ) Total Centene stockholders' equity 5,895 2,157 Noncontrolling interest 14 11 Total stockholders' equity 5,909 2,168 Total liabilities and stockholders' equity $ 10,780 $ 3,510 See notes to condensed financial information of registrant. Centene Corporation (Parent Company Only) Condensed Statements of Operations (In millions, except share data) Year Ended December 31, 2016 2015 2014 Expenses: Selling, general and administrative expenses $ 10 $ 9 $ 3 Gain on contingent consideration (5 ) (44 ) — Other income (expense): Investment and other income 2 (5 ) 1 Interest expense (201 ) (39 ) (30 ) Earnings (loss) before income taxes (204 ) (9 ) (32 ) Income tax benefit (76 ) (26 ) (8 ) Net earnings (loss) before equity in subsidiaries (128 ) 17 (24 ) Equity in earnings from subsidiaries 686 341 285 Net earnings 558 358 261 (Earnings) loss attributable to noncontrolling interests 1 (2 ) 7 Net earnings attributable to Centene $ 559 $ 356 $ 268 Net earnings per share from continuing operations: Basic earnings per common share $ 3.50 $ 2.99 $ 2.30 Diluted earnings per common share $ 3.41 $ 2.89 $ 2.23 Weighted average number of shares outstanding: Basic 159,567,607 119,100,744 116,345,764 Diluted 163,975,407 123,066,370 120,360,212 See notes to condensed financial information of registrant. Centene Corporation (Parent Company Only) Condensed Statements of Cash Flows (In millions) Year Ended December 31, 2016 2015 2014 Cash flows from operating activities: Cash provided by (used in) operating activities $ (646 ) $ 462 $ 317 Cash flows from investing activities: Capital contributions to subsidiaries, net of dividends (566 ) (660 ) (384 ) Purchases of investments (112 ) (17 ) (32 ) Sales and maturities of investments 169 9 14 Investments in acquisitions (2,248 ) (113 ) (137 ) Other investing activities, net — 7 — Net cash used in investing activities (2,757 ) (774 ) (539 ) Cash flows from financing activities: Proceeds from borrowings 8,934 1,925 1,875 Payment of long term debt (5,377 ) (1,575 ) (1,650 ) Common stock repurchases (63 ) (53 ) (29 ) Debt issuance costs (76 ) (4 ) (7 ) Other financing activities, net (14 ) 20 33 Net cash provided by financing activities 3,404 313 222 Net increase in cash and cash equivalents 1 1 — Cash and cash equivalents, beginning of period 4 3 3 Cash and cash equivalents, end of period $ 5 $ 4 $ 3 See notes to condensed financial information of registrant. Notes to Condensed Financial Information of Registrant Note A - Basis of Presentation and Significant Accounting Policies The parent company only financial statements should be read in conjunction with Centene Corporation's audited consolidated financial statements and the notes to consolidated financial statements included in this Form 10-K. The parent company's investment in subsidiaries is stated at cost plus equity in undistributed earnings of the subsidiaries. The parent company's share of net income of its unconsolidated subsidiaries is included in income using the equity method of accounting. Certain unrestricted subsidiaries receive monthly management fees from our restricted subsidiaries. The management and service fees received by our unrestricted subsidiaries are associated with all of the functions required to manage the restricted subsidiaries including but not limited to salaries and wages for all personnel, rent, utilities, medical management, provider contracting, compliance, member services, claims processing, information technology, cash management, finance and accounting, and other services. The management fees are based on a percentage of the restricted subsidiaries revenue. Due to our centralized cash management function, cash flows generated by our unrestricted subsidiaries are transferred to the parent company to the extent required, primarily to repay borrowings on the parent company's revolving credit facility, make acquisitions, fund capital contributions to subsidiaries and fund its operations. During the year ended December 31, 2016, operating cash flows were negatively impacted by the funding of the Health Net acquisition related expenses as well as refinancing the $400 million of Health Net Senior Notes. These Senior Notes were redeemed in December 2016. During the years ended December 31, 2015 and 2014, cash flows received by the parent from unrestricted subsidiaries were $445 million and $341 million , respectively, and were included in cash flows from operating activities. Certain amounts presented in the parent company only financial statements are eliminated in the consolidated financial statements of Centene Corporation. Certain amounts in the parent company only financial statements have been reclassified to conform to the 2016 presentation. These reclassifications have no effect on net earnings or stockholders' equity as previously reported. Note B - Dividends During 2016, 2015 and 2014 , the Registrant received dividends from its regulated subsidiaries totaling $121 million , $11 million and $50 million , respectively, reflected as investing cash flows.

Summary Of Significant Accoun32

Summary Of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying consolidated financial statements include the accounts of Centene Corporation and all majority owned subsidiaries and subsidiaries over which the Company exercises the power and control to direct activities significantly impacting financial performance. All material intercompany balances and transactions have been eliminated. The assets, liabilities and results of operations of Kentucky Spirit Health Plan (Kentucky Spirit) are classified as discontinued operations for all periods presented. Certain amounts in the consolidated financial statements and notes have been reclassified to conform to the 2016 presentation. These reclassifications have no effect on net earnings or stockholders' equity as previously reported.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with generally accepted accounting principles in the United States, or GAAP, requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Future events and their effects cannot be predicted with certainty; accordingly, the accounting estimates require the exercise of judgment. The accounting estimates used in the preparation of the consolidated financial statements will change as new events occur, as more experience is acquired, as additional information is obtained and as the operating environment changes. The Company evaluates and updates its assumptions and estimates on an ongoing basis and may employ outside experts to assist in our evaluation, as considered necessary. Actual results could differ from those estimates.
Business Combinations	Business Combinations Business combinations are accounted for using the acquisition method of accounting. The Company allocates the fair value of purchase consideration to the assets acquired and liabilities assumed based on their fair values at the acquisition date. The excess of the fair value of consideration transferred over the fair value of the net assets acquired is recorded as goodwill. Goodwill is generally attributable to the value of the synergies between the combined companies and the value of the acquired assembled workforce, neither of which qualifies for recognition as an intangible asset. The Company uses its best estimates and assumptions to value assets acquired and liabilities assumed at the acquisition date; however, these estimates are sometimes preliminary and in some instances, all information required to value the assets acquired and liabilities assumed may not be available or final as of the end of a reporting period subsequent to the business combination. If the accounting for the business combination is incomplete, provisional amounts are recorded. The provisional amounts are updated during the period determined, up to one year from the acquisition date. The Company includes the results of operations of acquired businesses in the Company's consolidated results prospectively from the date of acquisition. Acquisition related expenses and post-acquisition restructuring costs are recognized separately from the business combination and are expensed as incurred.
Cash and Cash Equivalents	Cash and Cash Equivalents Investments with original maturities of three months or less are considered to be cash equivalents. Cash equivalents consist of money market funds and bank certificates of deposit and savings accounts. The Company maintains amounts on deposit with various financial institutions, which may exceed federally insured limits. However, management periodically evaluates the credit-worthiness of those institutions, and the Company has not experienced any losses on such deposits.
Investments	Investments Short term investments include securities with maturities greater than three months to one year. Long term investments include securities with maturities greater than one year. Short term and long term investments are generally classified as available for sale and are carried at fair value. Certain equity investments are recorded using the cost or equity method. Unrealized gains and losses on investments available for sale are excluded from earnings and reported in accumulated other comprehensive income, a separate component of stockholders' equity, net of income tax effects. Premiums and discounts are amortized or accreted over the life of the related security using the effective interest method. The Company monitors the difference between the cost and fair value of investments. Investments that experience a decline in value that is judged to be other than temporary are written down to fair value and a realized loss is recorded in investment and other income. To calculate realized gains and losses on the sale of investments, the Company uses the specific amortized cost of each investment sold. Realized gains and losses are recorded in investment and other income. The Company uses the equity method to account for its investments in entities that it does not control but has the ability to exercise significant influence over operating and financial policies. These investments are recorded at the lower of their cost or fair value adjusted for the Company's proportionate share of earnings or losses.
Restricted Deposits	Restricted Deposits Restricted deposits consist of investments required by various state statutes to be deposited or pledged to state agencies. These investments are classified as long term, regardless of the contractual maturity date, due to the nature of the states' requirements. The Company is required to annually adjust the amount of the deposit pledged to certain states.
Fair Value Measurements	Fair Value Measurements In the normal course of business, the Company invests in various financial assets and incurs various financial liabilities. Fair values are disclosed for all financial instruments, whether or not such values are recognized in the Consolidated Balance Sheets. Management obtains quoted market prices and other observable inputs for these disclosures. The carrying amounts reported in the Consolidated Balance Sheets for cash and cash equivalents, premium and related receivables, medical claims liability, accounts payable and accrued expenses, unearned revenue, and certain other current assets and liabilities are carried at cost, which approximates fair value because of their short term nature. The following methods and assumptions were used to estimate the fair value of each financial instrument: • Available for sale investments and restricted deposits: The carrying amount is stated at fair value, based on quoted market prices, where available. For securities not actively traded, fair values were estimated using values obtained from independent pricing services or quoted market prices of comparable instruments. • Senior unsecured notes: Estimated based on third-party quoted market prices for the same or similar issues. • Variable rate debt: The carrying amount of our floating rate debt approximates fair value since the interest rates adjust based on market rate adjustments. • Interest rate swap: Estimated based on third-party market prices based on the forward 3-month LIBOR curve. • Contingent consideration: Estimated based on expected achievement of metrics included in the acquisition agreement considering circumstances that exist as of the acquisition date.
Property, Software and Equipment	Property, Software and Equipment Property, software and equipment are stated at cost less accumulated depreciation. Capitalized software includes certain costs incurred in the development of internal-use software, including external direct costs of materials and services and payroll costs of employees devoted to specific software development. Depreciation is calculated principally by the straight-line method over estimated useful lives. Leasehold improvements are depreciated using the straight-line method over the shorter of the expected useful life or the remaining term of the lease. Property, software and equipment are depreciated over the following periods: Fixed Asset Depreciation Period Buildings and land improvements 5 - 40 years Computer hardware and software 2 - 7 years Furniture and equipment 3 - 10 years Land improvements 3 - 20 years Leasehold improvements 1 - 20 years The carrying amounts of all long-lived assets are evaluated to determine if adjustment to the depreciation and amortization period or to the unamortized balance is warranted. Such evaluation is based principally on the expected utilization of the long-lived assets. The Company retains fully depreciated assets in property and accumulated depreciation accounts until it removes them from service. In the case of sale, retirement, or disposal, the asset cost and related accumulated depreciation balance is removed from the respective account, and the resulting net amount, less any proceeds, is included as a component of earnings from operations in the Consolidated Statements of Operations.
Goodwill and Intangible Assets	Goodwill and Intangible Assets Intangible assets represent assets acquired in purchase transactions and consist primarily of purchased contract rights, provider contracts, customer relationships, trade names, developed technologies and goodwill. Intangible assets are amortized using the straight-line method over the following periods: Intangible Asset Amortization Period Purchased contract rights 5 - 15 years Provider contracts 4 - 15 years Customer relationships 3 - 15 years Trade names 1 - 20 years Developed technology 5 years The Company tests for impairment of intangible assets as well as long-lived assets whenever events or changes in circumstances indicate that the carrying value of an asset or asset group (hereinafter referred to as “asset group”) may not be recoverable by comparing the sum of the estimated undiscounted future cash flows expected to result from use of the asset group and its eventual disposition to the carrying value. Such factors include, but are not limited to, significant changes in membership, state funding, state contracts and provider networks and contracts. If the sum of the estimated undiscounted future cash flows is less than the carrying value, an impairment determination is required. The amount of impairment is calculated by subtracting the fair value of the asset group from the carrying value of the asset group. An impairment charge, if any, is recognized within earnings from operations. The Company tests goodwill for impairment using a fair value approach. The Company is required to test for impairment at least annually, absent a triggering event, which could include a significant decline in operating performance that would require an impairment assessment. Absent any impairment indicators, the Company performs its goodwill impairment testing during the fourth quarter of each year. The Company recognizes an impairment charge for any amount by which the carrying amount of goodwill exceeds its implied fair value. The Company first assesses qualitative factors to determine whether it is necessary to perform the two-step quantitative goodwill impairment test. The Company generally does not calculate the fair value of a reporting unit unless it determines, based on a qualitative assessment, that it is more likely than not that its fair value is less than its carrying amount. However, in certain circumstances, such as recent acquisitions, the Company may elect to perform a quantitative assessment without first assessing qualitative factors. If the two-step quantitative test is deemed necessary, the Company determines an appropriate valuation technique to estimate a reporting unit's fair value as of the testing date. The Company utilizes either the income approach or the market approach, whichever is most appropriate for the respective reporting unit. The income approach is based on an internally developed discounted cash flow model that includes many assumptions related to future growth rates, discount factors, future tax rates, etc. The market approach is based on financial multiples of comparable companies derived from current market data. Changes in economic and operating conditions impacting assumptions used in our analyses could result in goodwill impairment in future periods.
Medical Claims Liability	Medical Claims Liability Medical claims liability includes claims reported but not yet paid, or inventory, estimates for claims incurred but not reported, or IBNR, and estimates for the costs necessary to process unpaid claims at the end of each period. The Company estimates its medical claims 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. Actuarial Standards of Practice generally require that the medical claims liability estimates be adequate to cover obligations under moderately adverse conditions. Moderately adverse conditions are situations in which the actual claims are expected to be higher than the otherwise estimated value of such claims at the time of estimate. In many situations, the claims amounts ultimately settled will be different than the estimate that satisfies the Actuarial Standards of Practice. The Company includes in its IBNR an estimate for medical claims liability under moderately adverse conditions which represents the risk of adverse deviation of the estimates in its actuarial method of reserving. The Company uses its judgment to determine the assumptions to be used in the calculation of the required estimates. The assumptions it considers when estimating IBNR include, without limitation, claims receipt and payment experience (and variations in that experience), changes in membership, provider billing practices, healthcare service utilization trends, cost trends, product mix, seasonality, prior authorization of medical services, benefit changes, known outbreaks of disease or increased incidence of illness such as influenza, provider contract changes, changes to fee schedules, and the incidence of high dollar or catastrophic claims. The Company's development of the medical claims liability estimate is a continuous process which it monitors and refines on a monthly basis as additional claims receipts and payment information becomes available. As more complete claims information becomes available, the Company adjusts the amount of the estimates, and includes the changes in estimates in medical costs in the period in which the changes are identified. In every reporting period, the operating results include the effects of more completely developed medical claims liability estimates associated with previously reported periods. The Company consistently applies its reserving methodology from period to period. As additional information becomes known, it adjusts the actuarial model accordingly to establish medical claims liability estimates. The Company periodically reviews actual and anticipated experience compared to the assumptions used to establish medical costs. The Company establishes premium deficiency reserves if actual and anticipated experience indicates that existing policy liabilities together with the present value of future gross premiums will not be sufficient to cover the present value of future benefits, settlement and maintenance costs.
Revenue Recognition	Revenue Recognition The Company's health plans generate revenues primarily from premiums received from the states in which it operates health plans. The Company generally receives a fixed premium per member per month pursuant to its state contracts and recognizes premium revenues during the period in which it is obligated to provide services to its members at the amount reasonably estimable. In some instances, the Company's base premiums are subject to an adjustment, or risk score, based on the acuity of its membership. Generally, the risk score is determined by the State analyzing submissions of processed claims data to determine the acuity of the Company's membership relative to the entire state's Medicaid membership. The Company estimates the amount of risk adjustment based upon the processed claims data submitted and expected to be submitted to Centers for Medicare and Medicaid Services (CMS) and records revenues on a risk adjusted basis. Some contracts allow for additional premiums related to certain supplemental services provided such as maternity deliveries. The Company's contracts with states may require us to maintain a minimum health benefits ratio (HBR) or may require us to share profits excess of certain levels. In certain circumstances, our plans may be required to return premium to the state in the event profits exceed established levels. We estimate the effect of these programs and recognize reductions in revenue in the current period. Other states may require us to meet certain performance and quality metrics in order to receive additional or full contractual revenue. For performance-based contracts, we do not recognize revenue subject to refund until data is sufficient to measure performance. Revenues are recorded based on membership and eligibility data provided by the states, which is adjusted on a monthly basis by the states for retroactive additions or deletions to membership data. These eligibility adjustments are estimated monthly and subsequent adjustments are made in the period known. The Company continuously reviews and updates those estimates as new information becomes available. It is possible that new information could require us to make additional adjustments, which could be significant, to these estimates. The Company's Medicare Advantage contracts are with CMS. CMS deploys a risk adjustment model which apportions premiums paid to all health plans according to health severity and certain demographic factors. The CMS risk adjustment model pays more for members whose medical history would indicate that they are expected to have higher medical costs. Under this risk adjustment methodology, CMS calculates the risk adjusted premium payment using diagnosis data from hospital inpatient, hospital outpatient, physician treatment settings as well as prescription drug events. The Company and the health care providers collect, compile and submit the necessary and available diagnosis data to CMS within prescribed deadlines. The Company estimates risk adjustment revenues based upon the diagnosis data submitted and expected to be submitted to CMS and records revenues on a risk adjusted basis. The Company's specialty services generate revenues under contracts with state and federal programs, healthcare organizations and other commercial organizations, as well as from our own subsidiaries. Revenues are recognized when the related services are provided or as ratably earned over the covered period of services. The Company recognizes revenue related to administrative services under the T-3 TRICARE government-sponsored managed care support contract in the North Region for the DoD's TRICARE program (T-3 contract) on a straight-line basis over the option period, when the fees become fixed and determinable. The T-3 contract includes various performance-based incentives and penalties. For each of the incentives or penalties, the Company adjusts revenue accordingly based on the amount that it has earned or incurred at each interim date and are legally entitled to in the event of a contract termination. Some states enact premium taxes, similar assessments and provider pass-through payments, collectively premium taxes, and these taxes are recorded as a separate component of both revenues and operating expenses. Additionally, the Company's insurance subsidiaries are subject to the Affordable Care Act annual health insurer fee (HIF). If the Company is able to negotiate reimbursement of portions of these premium taxes or the HIF, it recognizes revenue associated with the HIF on a straight-line basis when we have binding agreements for such reimbursements, including the “gross-up” to reflect the HIFs non-tax deductible nature. Collectively, this revenue is recorded as premium tax and health insurer fee revenue in the Consolidated Statements of Operations.
Affordable Care Act	Affordable Care Act The Affordable Care Act (ACA) established risk spreading premium stabilization programs effective January 1, 2014. These programs, commonly referred to as the “three Rs”, include a permanent risk adjustment program, a transitional reinsurance program, and a temporary risk corridor program. Additionally, the ACA established a minimum annual medical loss ratio (MLR) and cost-sharing reductions. Each of the three R programs are taken into consideration to determine if the Company's estimated annual medical costs are less than the minimum loss ratio and require an adjustment to premium revenue to meet the minimum MLR. During the second quarter of 2016, the Company recognized a $70 million net pre-tax benefit related to the reconciliation of 2015 risk adjustment and reinsurance programs. During the third quarter of 2016, the company received information from CMS, indicating that some of the participants in the Arizona risk adjustment program were unable to pay the amounts owed. As a result, the uncollected portion has been allocated pro-rata to other insurers in the market. Accordingly, the Company reduced the pre-tax earnings by $19 million during the third quarter. The Company’s accounting policies for the programs are as follows: Risk Adjustment The permanent risk adjustment program established by the ACA transfers funds from qualified individual and small group insurance plans with below average risk scores to those plans with above average risk scores within each state. The Company estimates the receivable or payable under the risk adjustment program based on its estimated risk score compared to the state average risk score. The Company may record a receivable or payable as an adjustment to Premium revenue to reflect the year to date impact of the risk adjustment based on its best estimate. The Company expects to refine its estimate as new information becomes available. As of December 31, 2016 and 2015 , the Company recorded a payable of $425 million and $108 million , respectively, associated with risk adjustment. Reinsurance The ACA established a transitional three-year reinsurance program whereby the Company’s claims costs incurred for qualified members will be reimbursed when they exceed a specific threshold. For the 2016 benefit year, qualified member claims that exceeded $90,000 entitled the Company to reimbursement from the programs at 50% coinsurance. The Company accounts for reinsurance recoveries as a reduction of Medical Costs based on each individual case that exceeds the reinsurance threshold established by the program. As of December 31, 2016 and 2015 , the Company recorded a receivable of $122 million and $24 million , respectively, associated with reinsurance. Risk Corridor The temporary, three-year risk corridor program established by the ACA applies to qualified individual and small group health plans operating both inside and outside of the Health Insurance Marketplace. The risk corridor program limits the Company’s gains and losses in the Health Insurance Marketplace by comparing certain medical and administrative costs to a target amount and sharing the risk for allowable costs with the federal government. Allowable medical costs are adjusted for risk adjustment settlements, transitional reinsurance recoveries, and cost sharing reductions received from the federal government. The Company records a risk corridor receivable or payable as an adjustment to premium revenue on a year to date basis based on where its estimated annual costs fall within the risk corridor range. As of December 31, 2016 and 2015 , the Company recorded a payable of $3 million and $4 million , respectively, associated with risk corridor. Minimum Medical Loss Ratio Additionally, the ACA established a minimum annual MLR for the Health Insurance Marketplace. Each of the three R programs described above are taken into consideration to determine if the Company’s estimated annual medical costs are less than the minimum loss ratio and require an adjustment to premium revenue to meet the minimum MLR. As of December 31, 2016 and 2015 , the Company recorded a payable of $18 million and $15 million , respectively, associated with minimum MLR. Cost-sharing Reductions (CSRs) The ACA directs issuers to reduce the Company's members' cost sharing for essential health benefits for individuals with Federal Poverty Levels (FPLs) between 100% and 250% who are enrolled in a silver tier product; eliminate cost sharing for Indians/Alaska Natives with an FPL less than 300% and eliminate cost sharing for Indians/Alaska Natives regardless of FPL level when services are provided by an Indian Health Service. In order to compensate issuers for reduced cost sharing provided to enrollees, CMS pays an advance CSR payment to the Company each month based on the Company’s certification data provided at the time of the qualified health plan application. After the close of the benefit year, the Company is required to provide CMS with data on the value of the CSRs provided to enrollees based on either a ‘simplified’ or ‘standard’ approach. A reconciliation will occur in order to calculate the difference between the Company’s CSR advance payments received and the value of CSRs provided to enrollees. This reconciliation will produce either a payable or receivable to/from CMS. The Company has elected the standard methodology approach. As of December 31, 2016 and 2015 , the Company recorded a payable of $147 million and $40 million , respectively, associated with CSRs.
Premium And Related Receivables And Unearned Revenue	Premium and Related Receivables and Unearned Revenue Premium and service revenues collected in advance are recorded as unearned revenue. For performance-based contracts the Company does not recognize revenue subject to refund until data is sufficient to measure performance. Premiums and service revenues due to the Company are recorded as premium and related receivables and are recorded net of an allowance based on historical trends and management's judgment on the collectibility of these accounts. As the Company generally receives payments during the month in which services are provided, the allowance is typically not significant in comparison to total revenues and does not have a material impact on the presentation of the financial condition or results of operations. Amounts receivable under federal contracts are comprised primarily of contractually defined billings, accrued contract incentives under the terms of the contract and amounts related to change orders for services not originally specified in the contract.
Significant Customers	Significant Customers Centene receives the majority of its revenues under contracts or subcontracts with state Medicaid managed care programs. The current contracts expire on various dates between February 28, 2017 and December 31, 2022. Customers where the aggregate annual contract revenues exceeded 10% of total annual revenues included the state of California, where the percentage of the Company's total revenue was 21% , 3% and 2% for the years ended December 31, 2016, 2015 and 2014 , respectively; the state of Florida, where the percentage of the Company's total revenue was 14% for the years ended December 31, 2015 and 2014; and the state of Texas, where the percentage of the Company's total revenue was 13% , 22% and 25% for the years ended December 31, 2016, 2015 and 2014 , respectively. The decrease in the revenue percentage for the state of Texas compared to prior periods is attributable to the overall growth in the Company's revenues as a result of the Health Net acquisition.
Other Income (Expense)	Other Income (Expense) Other income (expense) consists principally of investment income, interest expense and equity method earnings from investments. Investment income is derived from the Company's cash, cash equivalents, restricted deposits and investments. Interest expense relates to borrowings under the senior notes, interest rate swap, credit facilities, interest on capital leases and credit facility fees.
Income Taxes	Income Taxes Deferred tax assets and liabilities are recorded for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax law or tax rates is recognized in income in the period that includes the enactment date. Valuation allowances are provided when it is considered more likely than not that deferred tax assets will not be realized. In determining if a deductible temporary difference or net operating loss can be realized, the Company considers future reversals of existing taxable temporary differences, future taxable income, taxable income in prior carryback periods and tax planning strategies.
Contingencies	Contingencies The Company accrues for loss contingencies associated with outstanding litigation, claims and assessments for which it has determined it is probable that a loss contingency exists and the amount of loss can be reasonably estimated. The Company expenses professional fees associated with litigation claims and assessments as incurred.
Stock Based Compensation	Stock Based Compensation The fair value of the Company's employee share options and similar instruments are estimated using the Black-Scholes option-pricing model. That cost is recognized over the period during which an employee is required to provide service in exchange for the award. Excess tax benefits related to stock compensation are presented as a cash inflow from financing activities for the years ended December 31, 2015 and 2014 and as a cash inflow from operating activities for the year ended December 31, 2016 due to the prospective adoption of employee share-based payment guidance in 2016. The Company accounts for forfeitures when they occur.
Foreign Currency Transactions and Translations	Foreign Currency Translation The Company is exposed to foreign currency exchange risk through its equity method investment in Ribera Salud S.A. (Ribera Salud), a Spanish health management group whose functional currency is the Euro. The assets and liabilities of the Company's investment are translated into United States dollars at the balance sheet date. The Company translates its proportionate share of earnings using average rates during the year. The resulting foreign currency translation adjustments are recorded as a separate component of accumulated other comprehensive income.
New Accounting Pronouncements	Recent Accounting Guidance Not Yet Adopted In January 2017, the FASB issued an ASU simplifying the test for goodwill impairment. The amendments in this ASU eliminate Step 2 from the goodwill impairment test. Thus, an entity will no longer be required to compare the implied fair value of a reporting unit’s goodwill to its carrying amount. Instead, under the new guidance, an entity should perform the goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount and should recognize an impairment charge for the amount by which the carrying amount exceeds the fair value. The impairment charge should be limited to the total amount of goodwill allocated to that reporting unit. Under the new guidance, an entity still has the option to first perform the qualitative assessment for a reporting unit to determine if the quantitative impairment test is necessary. The new standard is effective for an entity’s annual or interim goodwill impairment tests in fiscal years beginning after December 15, 2019. Early adoption is permitted, including adoption in an interim period. The Company is currently evaluating the effect of the new goodwill impairment guidance. In November 2016, the FASB issued an ASU clarifying the classification and presentation of changes in restricted cash on the statement of cash flows. The amendments in this ASU require that a statement of cash flows explain the change during the period in the total of cash, cash equivalents, and restricted cash. Therefore, amounts generally described as restricted cash should be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. The new standard is effective for annual periods beginning after December 15, 2017, including interim periods within those annual reporting periods. Early adoption is permitted, including adoption in an interim period. The Company is currently evaluating the effect of the new statement of cash flows guidance. In August 2016, the FASB issued an ASU which clarifies how entities should classify certain cash receipts and cash payments on the statement of cash flows. The new guidance also clarifies how the predominance principle should be applied when cash receipts and cash payments have aspects of more than one class of cash flows. The new standard is effective for annual periods beginning after December 15, 2017, including interim periods within those annual reporting periods. Early adoption is permitted. The Company is currently evaluating the effect of the new statement of cash flows guidance. In February 2016, the FASB issued an ASU which introduces a lessee model that requires the majority of leases to be recognized on the balance sheet. The new standard also aligns many of the underlying principles of the new lessor model with those in Accounting Standards Codification 606, the FASB's new revenue recognition standard, and addresses other concerns related to the current lessee model. The standard also requires lessors to increase the transparency of their exposure to changes in value of their residual assets and how they manage that exposure. It is effective for annual and interim periods beginning after December 15, 2018. Early adoption is permitted. The Company is currently evaluating the effect of the new lease guidance. In May 2014, the FASB issued an ASU which supersedes existing revenue recognition standards with a single model unless those contracts are within the scope of other standards (e.g., an insurance entity's insurance contracts). Under the new standard, recognition of revenue occurs when a customer obtains control of promised goods or services in an amount that reflects the consideration which the entity expects to receive in exchange for those goods or services. In addition, the standard requires disclosure of the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. The new effective date is for annual and interim periods beginning after December 15, 2017. Early adoption is permitted. The Company is currently evaluating the effect of the new revenue recognition guidance. The majority of the Company's revenues are derived from insurance contracts and are excluded from the new standard, therefore the new guidance is not expected to have a material impact on the Company's consolidated financial position, results of operations or cash flows. The Company has determined that there are no other recently issued accounting pronouncements that will have a material impact on its consolidated financial position, results of operations or cash flows. Recently Adopted Accounting Pronouncements In March 2016, the Financial Accounting Standards Board (FASB) issued an Accounting Standards Update (ASU) which simplifies several aspects of the accounting for employee share-based payment transactions, including the accounting for income taxes, forfeitures, and statutory tax withholding requirements, as well as classification in the statement of cash flows. Under the new guidance, an entity recognizes all excess tax benefits and tax deficiencies as income tax expense or benefit in the income statement. The ASU also allows an entity to elect as an accounting policy either to continue to estimate the total number of awards for which the requisite service period will not be rendered, as currently required, or to account for forfeitures when they occur. Finally, the ASU modifies the current exception to liability classification of an award when an employer uses a net-settlement feature to withhold shares to meet the employee's minimum statutory tax withholding requirement. The new standard is effective for annual periods beginning after December 15, 2016, including interim periods within those annual reporting periods. Early adoption is permitted. The Company elected to early adopt this guidance in the fourth quarter of 2016. The adoption of this ASU decreased the Company's income tax expense by $14 million in 2016 and increased diluted shares outstanding by approximately one million shares. Excess tax benefits related to stock compensation are now presented as cash flows from operating activities rather than as cash flows from financing activities, this aspect of the guidance has been adopted prospectively. In connection with the adoption, the Company has elected to account for forfeitures as they occur. In May 2015, the FASB issued an ASU which expands the disclosure requirements for insurance companies that issue short-duration contracts. The new standard will increase the level of disclosure around the Company's Medical Claims Liability to include the following: claims development by year; claim frequency; a rollforward of the claims liability; and a description of methods and assumptions used for determining the liability. It is effective for annual periods beginning after December 15, 2015 and interim periods beginning after December 15, 2016. The Company has adopted this guidance in the current fiscal year.

Summary Of Significant Accoun33

Summary Of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Schedule Of Property Software And Equipment Depreciation Periods	Property, software and equipment are depreciated over the following periods: Fixed Asset Depreciation Period Buildings and land improvements 5 - 40 years Computer hardware and software 2 - 7 years Furniture and equipment 3 - 10 years Land improvements 3 - 20 years Leasehold improvements 1 - 20 years
Schedule Of Amortization Period For Intangible Assets	Intangible assets are amortized using the straight-line method over the following periods: Intangible Asset Amortization Period Purchased contract rights 5 - 15 years Provider contracts 4 - 15 years Customer relationships 3 - 15 years Trade names 1 - 20 years Developed technology 5 years
Schedule Of Allowance For Uncollectible Accounts	Activity in the allowance for uncollectible accounts for the years ended December 31, is summarized below ($ in millions): 2016 2015 2014 Allowances, beginning of year $ 10 $ 5 $ 1 Amounts charged to expense 33 12 8 Write-offs of uncollectible receivables (14 ) (7 ) (4 ) Allowances, end of year $ 29 $ 10 $ 5

Health Net Merger (Tables)

Health Net Merger (Tables)	12 Months Ended
	Dec. 31, 2016
Business Combinations [Abstract]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed	The Company's allocation of the fair value of assets acquired and liabilities assumed as of the acquisition date of March 24, 2016 , is as follows ($ in millions): Assets Acquired and Liabilities Assumed Cash and cash equivalents $ 956 Premium and related receivables (a) 1,890 Short term investments 74 Other current assets 524 Long term investments 2,037 Restricted deposits 30 Property, software and equipment, net 41 Intangible assets (b) 1,530 Other long term assets 136 Total assets acquired 7,218 Medical claims liability (c) 1,482 Borrowings under revolving credit facility 285 Accounts payable and accrued expenses (c) (d) 2,297 Return of premium payable 435 Unearned revenue 130 Long term deferred tax liabilities (e) 311 Long term debt (f) 418 Other long term liabilities 432 Total liabilities assumed 5,790 Total identifiable net assets 1,428 Goodwill (g) 3,859 Total assets acquired and liabilities assumed $ 5,287 Significant fair value adjustments are noted as follows: (a) The fair value of premium and related receivables approximated their historical cost, with the exception of the risk corridor receivable associated with the Health Insurance Marketplace. The fair value of the risk corridor receivable was estimated at $9 million . (b) 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 is 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. Other valuation methods, including the market approach and cost approach, were also utilized in estimating the fair value of certain intangible assets. The Company has finalized its fair value of intangibles to be $1,530 million with a weighted average life of 12 years. This final fair value of intangibles is approximately $30 million higher than the preliminary fair value of intangibles and the weighted average life increased by two years, which resulted in an immaterial true-up of intangible amortization recorded during the fourth quarter of 2016. The Company identified intangible assets including purchased contract rights, provider contracts, trade names and developed technology. (c) Medical claims liability and accounts payable and accrued expenses include $160 million of reserves associated with substance abuse rehabilitation claims primarily related to periods prior to the acquisition date. (d) Accounts payable and accrued expenses include approximately $253 million related to premium deficiency reserves based on cost trends existing prior to the acquisition date. The premium deficiency reserves are primarily associated with losses in the individual commercial business, largely in California, unfavorable performance in the Arizona commercial business as well as unfavorable performance in the Medicare business primarily in Oregon and Arizona. (e) The deferred tax liabilities are presented net of $365 million of deferred tax assets. (f) Debt is required to be measured at fair value under the acquisition method of accounting. The fair value of Health Net's $400 million Senior Notes assumed in the acquisition was $418 million . The $18 million increase will be amortized as a reduction to interest expense over the remaining life of the debt. In November 2016, this debt was redeemed as discussed in Note 11 , Debt. (g) The acquisition resulted in $3,859 million of goodwill related primarily to buyer specific synergies expected from the acquisition and the assembled workforce of Health Net. This goodwill is not deductible for income tax purposes. The Company assigned $3,317 million of goodwill to the Managed Care segment and $542 million of goodwill to the Specialty Services segment.
Schedule of Finite-Lived Intangible Assets Acquired as Part of Business Combination [Table Text Block]	The 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 $ 1,095 13 Provider contracts 181 11 Trade names 150 10 Developed technology 104 5 Total intangible assets acquired $ 1,530 12
Business Acquisition, Pro Forma Information (unaudited)	The following table presents supplemental pro forma information for the year ended December 31, 2015 ($ in millions, except per share data). December 31, 2015 Total revenues $ 38,826 Net earnings attributable to Centene Corporation $ 245 Diluted earnings per share $ 1.43
Restructuring and Related Costs	Changes in the restructuring liability for the year ended December 31, 2016 were as follows ($ in millions): December 31, 2016 Employee Termination Costs Stock Based Compensation Total Total accrued restructuring costs as of December 31, 2015 $ — $ — $ — Charges incurred 46 43 89 Paid/settled (28 ) (43 ) (71 ) Total accrued restructuring costs as of December 31, 2016 $ 18 $ — $ 18

Acquisitions and Noncontrolli35

Acquisitions and Noncontrolling Interest (Tables)	12 Months Ended
	Dec. 31, 2016
Noncontrolling Interest [Abstract]
Noncontrolling interest disclosure	The Company has consolidated subsidiaries where it maintains less than 100% ownership. The Company’s ownership interest for each subsidiary as of December 31, are as follows: 2016 2015 2014 Celtic Insurance Company 100 % 75 % 100 % Cenpatico Integrated Care 80 % 80 % 80 % Centurion 51 % 51 % 51 % Home State Health Plan 95 % 95 % 95 % The Practice (Group) Limited (TPG) (1) 75 % 49 % 49 % U.S. Medical Management 68 % 68 % 68 % (1) In 2016, the Company purchased a controlling interest in TPG for $8 million .
Schedule of net income attributable to parent and transfers from and to non-controlling interest entities	Net income attributable to Centene Corporation and transfers from (to) noncontrolling interest entities are as follows ($ in millions): Year Ended December 31, 2016 2015 2014 Net earnings attributable to Centene Corporation $ 559 $ 356 $ 268 Transfers from (to) the noncontrolling interest: Increase in equity for distributions from and consolidation of noncontrolling interest 2 11 — Reclassification to redeemable noncontrolling interest — 1 (9 ) Net transfers from (to) noncontrolling interest 2 12 (9 ) Changes from net earnings attributable to Centene Corporation and net transfers from (to) the noncontrolling interest $ 561 $ 368 $ 259
Redeemable noncontrolling interest	A reconciliation of the changes in the Redeemable Noncontrolling Interest is as follows ($ in millions): Balance, December 31, 2015 $ 156 Noncontrolling interest related to TPG acquisition 3 Noncontrolling interest repurchased related to Celtic Insurance Company (12 ) Net losses attributable to noncontrolling interest (2 ) Balance, December 31, 2016 $ 145

Short-Term And Long-Term Inve36

Short-Term And Long-Term Investments, Restricted Deposits (Tables)	12 Months Ended
	Dec. 31, 2016
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): December 31, 2016 December 31, 2015 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 364 $ — $ (1 ) $ 363 $ 431 $ — $ (2 ) $ 429 Corporate securities 1,933 12 (13 ) 1,932 859 2 (8 ) 853 Restricted certificates of deposit 5 — — 5 5 — — 5 Restricted cash equivalents 6 — — 6 78 — — 78 Municipal securities 1,767 1 (35 ) 1,733 496 2 (1 ) 497 Asset backed securities 317 1 (1 ) 317 163 — (1 ) 162 Residential mortgage backed securities 219 1 (5 ) 215 66 1 — 67 Commercial mortgage backed securities 343 — (5 ) 338 40 — — 40 Cost and equity method investments 163 — — 163 71 — — 71 Life insurance contracts 116 — — 116 16 — — 16 Total $ 5,233 $ 15 $ (60 ) $ 5,188 $ 2,225 $ 5 $ (12 ) $ 2,218
Schedule of available-for-sale investments in a continuous unrealized loss position	The fair value of available-for-sale investments 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): December 31, 2016 December 31, 2015 Less Than 12 Months 12 Months or More Less Than 12 Months 12 Months or More Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value U.S. Treasury securities and obligations of U.S. government corporations and agencies $ (1 ) $ 215 $ — $ 2 $ (2 ) $ 294 $ — $ 14 Corporate securities (12 ) 1,020 (1 ) 39 (6 ) 561 (2 ) 41 Municipal securities (35 ) 1,423 — 30 (1 ) 208 — 5 Asset backed securities (1 ) 101 — 18 (1 ) 121 — 8 Residential mortgage backed securities (5 ) 188 — — — 30 — — Commercial mortgage backed securities (5 ) 271 — — — 34 — — Total $ (59 ) $ 3,218 $ (1 ) $ 89 $ (10 ) $ 1,248 $ (2 ) $ 68
Contractual maturities of short-term and long-term investments and restricted deposits	The contractual maturities of short term and long term investments and restricted deposits are as follows ($ in millions): December 31, 2016 December 31, 2015 Investments Restricted Deposits Investments Restricted Deposits Amortized Cost Fair Value Amortized Cost Fair Value Amortized Cost Fair Value Amortized Cost Fair Value One year or less $ 500 $ 500 $ 91 $ 91 $ 176 $ 176 $ 93 $ 93 One year through five years 1,982 1,974 47 47 1,662 1,654 22 22 Five years through ten years 1,101 1,089 — — 267 268 — — Greater than ten years 633 617 — — 5 5 — — Asset-backed securities 879 870 — — — — — — Total $ 5,095 $ 5,050 $ 138 $ 138 $ 2,110 $ 2,103 $ 115 $ 115

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements By Level For Assets Measured At Fair Value On A Recurring Basis	The following table summarizes fair value measurements by level at December 31, 2016 , 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 $ 3,930 $ — $ — $ 3,930 Investments available for sale: U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 221 $ 15 $ — $ 236 Corporate securities — 1,932 — 1,932 Municipal securities — 1,733 — 1,733 Asset backed securities — 317 — 317 Residential mortgage backed securities — 215 — 215 Commercial mortgage backed securities — 338 — 338 Total investments $ 221 $ 4,550 $ — $ 4,771 Restricted deposits available for sale: Cash and cash equivalents $ 6 $ — $ — $ 6 Certificates of deposit 5 — — 5 U.S. Treasury securities and obligations of U.S. government corporations and agencies 127 — — 127 Total restricted deposits $ 138 $ — $ — $ 138 Other long term assets: Interest rate swap agreements $ — $ 4 $ — $ 4 Total assets at fair value $ 4,289 $ 4,554 $ — $ 8,843 Liabilities Other long term liabilities: Interest rate swap agreements $ — $ 62 $ — $ 62 Total liabilities at fair value $ — $ 62 $ — $ 62 The following table summarizes fair value measurements by level at December 31, 2015 , 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 $ 1,760 $ — $ — $ 1,760 Investments available for sale: U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 325 $ 72 $ — $ 397 Corporate securities — 853 — 853 Municipal securities — 497 — 497 Asset backed securities — 162 — 162 Residential mortgage backed securities — 67 — 67 Commercial mortgage backed securities — 40 — 40 Total investments $ 325 $ 1,691 $ — $ 2,016 Restricted deposits available for sale: Cash and cash equivalents $ 78 $ — $ — $ 78 Certificates of deposit 5 — — 5 U.S. Treasury securities and obligations of U.S. government corporations and agencies 32 — — 32 Total restricted deposits $ 115 $ — $ — $ 115 Other long term assets: Interest rate swap agreements $ — $ 11 $ — $ 11 Total assets at fair value $ 2,200 $ 1,702 $ — $ 3,902 Liabilities Other long term liabilities: Interest rate swap agreements $ — $ 2 $ — $ 2 Total liabilities at fair value $ — $ 2 $ — $ 2

Property, Software And Equipm38

Property, Software And Equipment (Tables)	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Property, Software and Equipment	Property, software and equipment consist of the following as of December 31 ($ in millions): 2016 2015 Land $ 113 $ 104 Building 271 223 Computer software 377 237 Computer hardware 179 105 Furniture and office equipment 126 92 Leasehold improvements 173 108 1,239 869 Less accumulated depreciation (442 ) (351 ) Property, software and equipment, net $ 797 $ 518

Goodwill And Intangible Assets

Goodwill And Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of changes In goodwill by operating segment	The following table summarizes the changes in goodwill by operating segment ($ in millions): Managed Care Specialty Services Total Balance as of December 31, 2014 $ 276 $ 478 $ 754 Acquisitions and purchase accounting adjustments 103 3 106 Impairment (18 ) — (18 ) Balance as of December 31, 2015 361 481 842 Acquisitions and purchase accounting adjustments 3,331 542 3,873 Translation impact (3 ) — (3 ) Balance as of December 31, 2016 $ 3,689 $ 1,023 $ 4,712 Goodwill was related to the acquisitions and finalization of fair value allocations discussed in Note 3 , Health Net and Note 4 , Acquisitions and Noncontrolling Interest .
Schedule of intangible assets	Intangible assets at December 31, consist of the following ($ in millions): Weighted Average Life in Years 2016 2015 2016 2015 Purchased contract rights $ 1,171 $ 71 12.6 8.8 Provider contracts 285 103 10.7 11.1 Customer relationships 22 26 8.2 8.1 Trade names 163 12 9.6 7.3 Developed technology 110 5 5.0 5.0 Intangible assets 1,751 217 11.5 9.8 Less accumulated amortization: Purchased contract rights (95 ) (21 ) Provider contracts (55 ) (24 ) Customer relationships (21 ) (14 ) Trade names (17 ) (2 ) Developed technology (18 ) (1 ) Total accumulated amortization (206 ) (62 ) Intangible assets, net $ 1,545 $ 155
Schedule of future amortization expenses	Estimated total amortization expense related to intangible assets for each of the five succeeding fiscal years is as follows ($ in millions): Year Expense 2017 $ 155 2018 152 2019 152 2020 150 2021 133

Medical Claims Liability (Table

Medical Claims Liability (Tables)	12 Months Ended
	Dec. 31, 2016
Liability for Unpaid Claims and Claims Adjustment Expense, Activity in Liability [Abstract]
Schedule Of Change In Medical Claims Liability by Operating Segment	The following table summarizes the change in medical claims liability by operating segment ($ in millions): Managed Care Specialty Services Consolidated Total Balance, January 1, 2014, net $ 1,101 $ 11 $ 1,112 Incurred related to: Current year 12,468 352 12,820 Prior years (141 ) (1 ) (142 ) Total incurred 12,327 351 12,678 Paid related to: Current year 10,796 326 11,122 Prior years 936 9 945 Total paid 11,732 335 12,067 Balance, December 31, 2014, net $ 1,696 $ 27 $ 1,723 Acquisitions 79 — 79 Incurred related to: Current year 16,974 497 17,471 Prior years (223 ) (6 ) (229 ) Total incurred 16,751 491 17,242 Paid related to: Current year 14,826 453 15,279 Prior years 1,448 19 1,467 Total paid 16,274 472 16,746 Balance at December 31, 2015, net $ 2,252 $ 46 $ 2,298 Acquisitions 1,482 — 1,482 Incurred related to: Current year 30,073 873 30,946 Prior years (303 ) (7 ) (310 ) Total incurred 29,770 866 30,636 Paid related to: Current year 27,714 818 28,532 Prior years 1,921 39 1,960 Total paid 29,635 857 30,492 Balance at December 31, 2016, net $ 3,869 $ 55 $ 3,924 Reinsurance recoverable 5 — 5 Balance, December 31, 2016 $ 3,874 $ 55 $ 3,929
Short-duration Insurance Contracts, Claims Development	For claims frequency information summarized below, a claim is defined as the financial settlement of a single medical event in which remuneration was paid to the servicing provider. 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. We estimate our 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. Information is summarized as follows (in millions): December 31, 2016 Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance Total IBNR Plus Expected Development on Reported Claims Cumulative Paid Claims Managed Care: 2014 $ 23,468 $ 2 121.0 2015 29,833 52 153.4 2016 33,782 3,001 164.9 Specialty Services: 2014 $ 346 $ — 2.7 2015 492 — 3.1 2016 873 49 6.3 Information about incurred and paid claims development as of December 31, 2016 is included in the table below and is inclusive of claims incurred and paid related to the Health Net business prior and subsequent to the acquisition date. The claims development information for all periods preceding the most recent reporting period is considered required supplementary information. Incurred and paid claims development as of December 31, 2016 is as follows ($ in millions) : Cumulative Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, Claim Year 2014 (unaudited) 2015 (unaudited) 2016 Managed Care: 2014 $ 23,790 $ 23,472 $ 23,468 2015 30,122 29,833 2016 33,782 Total incurred claims $ 87,083 Specialty Services: 2014 $ 352 $ 348 $ 346 2015 497 492 2016 873 Total incurred claims $ 1,711 Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, Claim Year 2014 (unaudited) 2015 (unaudited) 2016 Managed Care: 2014 $ 20,415 $ 22,895 $ 23,450 2015 27,211 29,539 2016 30,225 Total payment of incurred claims $ 83,214 Managed Care medical claims liability $ 3,869 Specialty Services: 2014 $ 326 $ 346 $ 346 2015 453 492 2016 818 Total payment of incurred claims $ 1,656 Specialty Services medical claims liability $ 55 Consolidated total, net of reinsurance $ 3,924

Affordable Care Act (Tables)

Affordable Care Act (Tables)	12 Months Ended
	Dec. 31, 2016
Affordable Care Act [Abstract]
Schedule of receivables (payables) related to the Health Insurance Marketplace programs	The Company's receivables (payables) for each of these programs are as follows at each year ended ($ in millions): December 31, 2016 December 31, 2015 Risk adjustment $ (425 ) $ (108 ) Reinsurance 122 24 Risk corridor (3 ) (4 ) Minimum MLR (18 ) (15 ) Cost sharing reductions (147 ) (40 )

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Schedule Of Debt	Debt consists of the following ($ in millions): December 31, 2016 December 31, 2015 $425 million 5.75% Senior notes, due June 1, 2017 $ — $ 428 $1,400 million 5.625% Senior notes, due February 15, 2021 1,400 — $1,000 million 4.75% Senior notes, due May 15, 2022 1,008 500 $1,000 million 6.125% Senior notes, due February 15, 2024 1,000 — $1,200 million 4.75% Senior notes, due January 15, 2025 1,200 — Fair value of interest rate swap agreements (58 ) 9 Senior notes 4,550 937 Revolving credit agreement 100 225 Mortgage notes payable 64 67 Capital leases and other 18 6 Debt issuance costs (77 ) (14 ) Total debt 4,655 1,221 Less current portion (4 ) (5 ) Long term debt $ 4,651 $ 1,216
Schedule Of Aggregate Maturities Of Debt	Aggregate maturities for the Company's debt are as follows ($ in millions): 2017 $ 4 2018 4 2019 16 2020 4 2021 1,404 Thereafter 3,350 Total $ 4,782

Income Taxes Income Taxes (Tabl

Income Taxes Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Reconciliation Of The Tax Provision At The U.S. Federal Statutory Rate To The Provision For Income Taxes	The reconciliation of the tax provision at the U.S. federal statutory rate to income tax expense for the years ended December 31 is as follows ($ in millions): 2016 2015 2014 Earnings from continuing operations, before income tax expense $ 1,157 $ 697 $ 457 (Earnings) loss attributable to flow through noncontrolling interest (8 ) 1 4 Earnings from continuing operations, less noncontrolling interest, before income tax expense 1,149 698 461 Tax provision at the U.S. federal statutory rate 402 244 162 State income taxes, net of federal income tax benefit 10 15 6 Nondeductible compensation 23 2 (13 ) ACA Health Insurer Fee 162 75 44 Other, net 2 3 (3 ) Income tax expense $ 599 $ 339 $ 196
Tax Effects Of Temporary Differences Which Give Rise To Deferred Tax Assets And Liabilities	The tax effects of temporary differences which give rise to deferred tax assets and liabilities are presented below for the years ended December 31 ($ in millions): 2016 2015 Deferred tax assets: Medical claims liability $ 66 $ 27 Nondeductible liabilities 39 14 Net operating loss and tax credit carryforwards 101 22 Compensation accruals 156 73 Acquisition costs — 10 Premium and related receivables 79 36 Other 14 9 Deferred tax assets 455 191 Valuation allowance (86 ) (11 ) Net deferred tax assets $ 369 $ 180 Deferred tax liabilities: Intangible assets $ 577 $ 46 Prepaid assets 17 8 Fixed assets and intangibles 65 31 Investments in joint ventures 11 6 Other 2 2 Deferred tax liabilities 672 93 Net deferred tax assets (liabilities) $ (303 ) $ 87
Consolidated Income Tax Expense	The consolidated income tax expense consists of the following for the years ended December 31 ($ in millions): 2016 2015 2014 Current provision Federal $ 485 $ 332 $ 225 State and local 22 26 13 Total current provision 507 358 238 Deferred provision 92 (19 ) (42 ) Total income tax expense $ 599 $ 339 $ 196 The Company maintains a reserve for uncertain tax positions that may be challenged by a tax authority. A rollforward of the beginning and ending amount of uncertain tax positions, exclusive of related interest and penalties, is as follows: Year Ended December 31, 2016 2015 Gross unrecognized tax benefits, beginning of period $ 5 $ 4 Gross increases: Current year tax positions 6 1 Acquired reserves 93 — Gross decreases: Prior year tax positions (1 ) — Statute of limitation lapses (1 ) — Gross unrecognized tax benefits, end of period $ 102 $ 5

Stock Incentive Plans (Tables)

Stock Incentive Plans (Tables)	12 Months Ended
	Dec. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary Of Stock Option Activity	Option activity for the year ended December 31, 2016 is summarized below: Shares Weighted Average Exercise Price Aggregate Intrinsic Value ($ in millions) Weighted Average Remaining Contractual Term Outstanding as of December 31, 2015 677,408 $ 11.88 Granted 40,000 59.94 Exercised (397,040 ) 12.25 Forfeited — — Outstanding as of December 31, 2016 320,368 $ 17.44 $ 13 2.9 Exercisable as of December 31, 2016 280,368 $ 11.37 $ 13 1.9
Option Pricing Assumptions	The fair value of each option grant is estimated on the date of the grant using the Black-Scholes option-pricing model with the following weighted-average assumptions: Year Ended December 31, 2016 2015 (1) 2014 (1) Expected life (in years) 4.8 — — Risk-free interest rate 1.6% — — Expected volatility 39.0% — — Expected dividend yield — — — (1) No options were awarded in the years ended December 31, 2015 and 2014.
Stock Option Awards	Other information pertaining to option activity is as follows: Year Ended December 31, 2016 2015 (1) 2014 (1) Weighted-average fair value of options granted $ 59.94 $ — $ — Total intrinsic value of stock options exercised ($ in millions) $ 19 $ 28 $ 17 (1) No options were awarded in the years ended December 31, 2015 and 2014.
Non-Vested Restricted Stock And Restricted Stock	A summary of the Company's non-vested restricted stock and restricted stock unit shares as of December 31, 2016 , and changes during the year ended December 31, 2016 , is presented below: Shares Weighted Average Grant Date Fair Value Non-vested balance as of December 31, 2015 4,122,003 $ 48.65 Granted 2,120,101 57.71 Converted (1) 1,285,674 62.70 Vested (2,546,543 ) 50.00 Forfeited (190,894 ) 47.65 Non-vested balance as of December 31, 2016 4,790,341 $ 55.75 (1) Health Net awards converted in connection with the acquisition.

Commitments (Tables)

Commitments (Tables)	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Annual Non-Cancelable Minimum Lease Payments	Annual non-cancelable minimum lease payments over the next five years and thereafter are as follows ($ in millions): 2017 $ 128 2018 117 2019 105 2020 92 2021 75 Thereafter 114 $ 631

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2016
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 for the years ended December 31 ($ in millions, except per share data): 2016 2015 2014 Earnings (loss) attributable to Centene Corporation: Earnings from continuing operations, net of tax $ 559 $ 356 $ 268 Discontinued operations, net of tax 3 (1 ) 3 Net earnings $ 562 $ 355 $ 271 Shares used in computing per share amounts: Weighted average number of common shares outstanding 159,567,607 119,100,744 116,345,764 Common stock equivalents (as determined by applying the treasury stock method) 4,407,800 3,965,626 4,014,448 Weighted average number of common shares and potential dilutive common shares outstanding 163,975,407 123,066,370 120,360,212 Net earnings (loss) per common share attributable to Centene Corporation: Basic: Continuing operations $ 3.50 $ 2.99 $ 2.30 Discontinued operations 0.02 (0.01 ) 0.03 Basic earnings per common share $ 3.52 $ 2.98 $ 2.33 Diluted: Continuing operations $ 3.41 $ 2.89 $ 2.23 Discontinued operations 0.02 (0.01 ) 0.02 Diluted earnings per common share $ 3.43 $ 2.88 $ 2.25

Segment Information (Tables)

Segment Information (Tables)	12 Months Ended
	Dec. 31, 2016
Segment Reporting [Abstract]
Segment Information	Segment information as of and for the year ended December 31, 2016 , follows ($ in millions): Managed Care Specialty Services Eliminations Consolidated Total Total revenues from external customers $ 37,523 $ 3,084 $ — $ 40,607 Total revenues internal customers 199 5,953 (6,152 ) — Total revenues 37,722 9,037 (6,152 ) 40,607 Earnings from operations 1,070 190 — 1,260 Total assets 17,962 2,235 — 20,197 Segment information as of and for the year ended December 31, 2015 , follows ($ in millions): Managed Care Specialty Services Eliminations Consolidated Total Total revenues from external customers $ 20,544 $ 2,216 $ — $ 22,760 Total revenues internal customers 100 4,864 (4,964 ) — Total revenues 20,644 7,080 (4,964 ) 22,760 Earnings from operations 513 192 — 705 Total assets 6,202 1,137 — 7,339 Segment information as of and for the year ended December 31, 2014 , follows ($ in millions): Managed Care Specialty Services Eliminations Consolidated Total Total revenues from external customers $ 14,775 $ 1,785 $ — $ 16,560 Total revenues internal customers 60 3,019 (3,079 ) — Total revenues 14,835 4,804 (3,079 ) 16,560 Earnings from operations 353 111 — 464 Total assets 4,706 1,118 — 5,824

Quarterly Selected Financial 48

Quarterly Selected Financial Information (Tables)	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Quarterly Selected Financial Information	For the Quarter Ended (1) March 31, 2016 June 30, 2016 September 30, 2016 December 31, 2016 Total revenues $ 6,953 $ 10,897 $ 10,846 $ 11,911 Amounts attributable to Centene Corporation common shareholders: Earnings (loss) from continuing operations, net of income tax expense (15 ) 171 148 255 Discontinued operations, net of income tax expense (benefit) (1 ) (1 ) (1 ) 6 Net earnings (loss) $ (16 ) $ 170 $ 147 $ 261 Net earnings (loss) per common share attributable to Centene Corporation: Basic: Continuing operations $ (0.12 ) $ 1.00 $ 0.87 $ 1.49 Discontinued operations (0.01 ) — (0.01 ) 0.04 Basic earnings per common share $ (0.13 ) $ 1.00 $ 0.86 $ 1.53 Diluted: Continuing operations $ (0.12 ) $ 0.98 $ 0.84 $ 1.45 Discontinued operations (0.01 ) (0.01 ) — 0.04 Diluted earnings per common share $ (0.13 ) $ 0.97 $ 0.84 $ 1.49 Weighted average number of common shares outstanding: Basic 125,543,076 170,558,778 170,774,587 171,143,624 Diluted 125,543,076 174,848,996 175,495,339 175,511,179 (1) The Company early adopted ASU 2016-09 during the fourth quarter of 2016. The ASU requires adjustments be reflected as of the beginning of the fiscal year of adoption and as a result, prior periods have been restated accordingly. Refer to Note 2, Summary of Significant Accounting Policies . For the Quarter Ended March 31, June 30, September 30, December 31, Total revenues $ 5,131 $ 5,506 $ 5,821 $ 6,302 Amounts attributable to Centene Corporation common shareholders: Earnings from continuing operations, net of income tax expense 64 88 92 112 Discontinued operations, net of income tax expense (benefit) (1 ) — 1 (1 ) Net earnings $ 63 $ 88 $ 93 $ 111 Net earnings (loss) per common share attributable to Centene Corporation: Basic: Continuing operations $ 0.54 $ 0.74 $ 0.77 $ 0.94 Discontinued operations (0.01 ) — 0.01 (0.01 ) Basic earnings per common share $ 0.53 $ 0.74 $ 0.78 $ 0.93 Diluted: Continuing operations $ 0.52 $ 0.72 $ 0.75 $ 0.91 Discontinued operations (0.01 ) — 0.01 (0.01 ) Diluted earnings per common share $ 0.51 $ 0.72 $ 0.76 $ 0.90

Condensed Financial Informati49

Condensed Financial Information Of Registrant (Tables) - Parent Company	12 Months Ended
	Dec. 31, 2016
Condensed Balance Sheets	Centene Corporation (Parent Company Only) Condensed Balance Sheets (In millions, except share data) December 31, 2016 2015 ASSETS Current assets: Cash and cash equivalents $ 5 $ 4 Short term investments, at fair value (amortized cost $1 and $5, respectively) 1 5 Other current assets 29 25 Total current assets 35 34 Long term investments, at fair value (amortized cost $19 and $6, respectively) 19 6 Investment in subsidiaries 10,674 3,435 Other long term assets 52 35 Total assets $ 10,780 $ 3,510 LIABILITIES AND STOCKHOLDERS' EQUITY Current liabilities $ 78 $ 13 Long term debt 4,573 1,147 Other long term liabilities 75 26 Total liabilities 4,726 1,186 Redeemable noncontrolling interest 145 156 Stockholders' equity: Preferred stock, $.001 par value; authorized 10,000,000 shares; no shares issued or outstanding at December 31, 2016 and December 31, 2015 — — Common stock, $.001 par value; authorized 400,000,000 shares; 178,134,306 issued and 171,919,071 outstanding at December 31, 2016, and 126,855,477 issued and 120,342,981 outstanding at December 31, 2015 — — Additional paid-in capital 4,190 956 Accumulated other comprehensive loss (36 ) (10 ) Retained earnings 1,920 1,358 Treasury stock, at cost (6,215,235 and 6,512,496 shares, respectively) (179 ) (147 ) Total Centene stockholders' equity 5,895 2,157 Noncontrolling interest 14 11 Total stockholders' equity 5,909 2,168 Total liabilities and stockholders' equity $ 10,780 $ 3,510
Condensed Statements Of Operations	Centene Corporation (Parent Company Only) Condensed Statements of Operations (In millions, except share data) Year Ended December 31, 2016 2015 2014 Expenses: Selling, general and administrative expenses $ 10 $ 9 $ 3 Gain on contingent consideration (5 ) (44 ) — Other income (expense): Investment and other income 2 (5 ) 1 Interest expense (201 ) (39 ) (30 ) Earnings (loss) before income taxes (204 ) (9 ) (32 ) Income tax benefit (76 ) (26 ) (8 ) Net earnings (loss) before equity in subsidiaries (128 ) 17 (24 ) Equity in earnings from subsidiaries 686 341 285 Net earnings 558 358 261 (Earnings) loss attributable to noncontrolling interests 1 (2 ) 7 Net earnings attributable to Centene $ 559 $ 356 $ 268 Net earnings per share from continuing operations: Basic earnings per common share $ 3.50 $ 2.99 $ 2.30 Diluted earnings per common share $ 3.41 $ 2.89 $ 2.23 Weighted average number of shares outstanding: Basic 159,567,607 119,100,744 116,345,764 Diluted 163,975,407 123,066,370 120,360,212
Condensed Statements Of Cash Flows	Centene Corporation (Parent Company Only) Condensed Statements of Cash Flows (In millions) Year Ended December 31, 2016 2015 2014 Cash flows from operating activities: Cash provided by (used in) operating activities $ (646 ) $ 462 $ 317 Cash flows from investing activities: Capital contributions to subsidiaries, net of dividends (566 ) (660 ) (384 ) Purchases of investments (112 ) (17 ) (32 ) Sales and maturities of investments 169 9 14 Investments in acquisitions (2,248 ) (113 ) (137 ) Other investing activities, net — 7 — Net cash used in investing activities (2,757 ) (774 ) (539 ) Cash flows from financing activities: Proceeds from borrowings 8,934 1,925 1,875 Payment of long term debt (5,377 ) (1,575 ) (1,650 ) Common stock repurchases (63 ) (53 ) (29 ) Debt issuance costs (76 ) (4 ) (7 ) Other financing activities, net (14 ) 20 33 Net cash provided by financing activities 3,404 313 222 Net increase in cash and cash equivalents 1 1 — Cash and cash equivalents, beginning of period 4 3 3 Cash and cash equivalents, end of period $ 5 $ 4 $ 3

Organization And Operations (De

Organization And Operations (Details) $ in Millions	Mar. 24, 2016USD ($)	Feb. 02, 2015	Dec. 31, 2016segment
Business Acquisition [Line Items]
Number of reportable segments | segment			2
Stockholders' equity note, stock split, conversion ratio		2
Health Net, Inc.
Business Acquisition [Line Items]
Business acquisition, total consideration transferred, including assumed debt	$ 5,990
Business acquisition, recognized identifiable assets acquired and liabilities assumed, long-term debt	$ 703

Summary Of Significant Accoun51

Summary Of Significant Accounting Policies (Schedule Of Property, Software And Equipment Depreciation Periods) (Details)	12 Months Ended
	Dec. 31, 2016
Minimum | Buildings and land improvements
Property, Plant and Equipment [Line Items]
Fixed Asset - depreciation period	5 years
Minimum | Computer hardware and software
Property, Plant and Equipment [Line Items]
Fixed Asset - depreciation period	2 years
Minimum | Furniture and equipment
Property, Plant and Equipment [Line Items]
Fixed Asset - depreciation period	3 years
Minimum | Land improvements
Property, Plant and Equipment [Line Items]
Fixed Asset - depreciation period	3 years
Minimum | Leasehold improvements
Property, Plant and Equipment [Line Items]
Fixed Asset - depreciation period	1 year
Maximum | Buildings and land improvements
Property, Plant and Equipment [Line Items]
Fixed Asset - depreciation period	40 years
Maximum | Computer hardware and software
Property, Plant and Equipment [Line Items]
Fixed Asset - depreciation period	7 years
Maximum | Furniture and equipment
Property, Plant and Equipment [Line Items]
Fixed Asset - depreciation period	10 years
Maximum | Land improvements
Property, Plant and Equipment [Line Items]
Fixed Asset - depreciation period	20 years
Maximum | Leasehold improvements
Property, Plant and Equipment [Line Items]
Fixed Asset - depreciation period	20 years

Summary Of Significant Accoun52

Summary Of Significant Accounting Policies (Schedule Of Amortization Period For Intangible Assets) (Details)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	11 years 6 months	9 years 9 months 18 days
Purchased contract rights
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	12 years 7 months 6 days	8 years 9 months 18 days
Provider contracts
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	10 years 8 months 12 days	11 years 1 month 6 days
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	8 years 2 months 12 days	8 years 1 month 6 days
Trade names
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	9 years 7 months 6 days	7 years 3 months 18 days
Developed Technology
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	5 years	5 years
Minimum | Purchased contract rights
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	5 years
Minimum | Provider contracts
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	4 years
Minimum | Customer relationships
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	3 years
Minimum | Trade names
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	1 year
Maximum | Purchased contract rights
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	15 years
Maximum | Provider contracts
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	15 years
Maximum | Customer relationships
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	15 years
Maximum | Trade names
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	20 years

Summary Of Significant Accoun53

Summary Of Significant Accounting Policies (Schedule Of Allowance For Uncollectible Accounts) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Allowance for Doubtful Accounts Receivable [Roll Forward]
Allowances, beginning of year	$ 10	$ 5	$ 1
Amounts charged to expense	33	12	8
Write-offs of uncollectible receivables	(14)	(7)	(4)
Allowances, end of year	$ 29	$ 10	$ 5

Summary Of Significant Accoun54

Summary Of Significant Accounting Policies (Schedule Of Percentage Of Company's Total Revenues) (Details)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
CALIFORNIA
Percentage of revenues under contracts or subcontracts	21.00%	3.00%	2.00%
FLORIDA
Percentage of revenues under contracts or subcontracts		14.00%	14.00%
TEXAS
Percentage of revenues under contracts or subcontracts	13.00%	22.00%	25.00%

Summary Of Significant Accoun55

Summary Of Significant Accounting Policies (Recently Adopted Accounting Pronouncements) (Details) - New Accounting Pronouncement, Early Adoption, Effect shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2016USD ($)shares
New Accounting Pronouncement, Early Adoption [Line Items]
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense | $	$ 14
Increase in diluted shares outstanding | shares	1

Summary Of Significant Accoun56

Summary Of Significant Accounting Policies (Health Insurance Marketplace) (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Sep. 30, 2016	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015
Accounting Policies [Abstract]
Affordable Care Act risk adjustment and reinsurance, pre-tax benefit, period increase (decrease)	$ (19)	$ 70	$ 51
Affordable Care Act risk adjustment payable			$ 425	$ 108
Reinsurance reimbursement threshold			$90,000 entitled the Company to reimbursement from the programs at 50%
Affordable Care Act reinsurance receivable			$ 122	24
Affordable Care Act risk corridor payable			3	4
Affordable Care Act minimum medical loss ratio payable			18	15
Affordable Care Act cost sharing reductions			$ 147	$ 40

Health Net Merger (Details)

Health Net Merger (Details) $ / shares in Units, $ in Millions	Mar. 24, 2016USD ($)$ / sharesshares	Dec. 31, 2016USD ($)	Dec. 31, 2016USD ($)
Business Acquisition [Line Items]
Centene share price | $ / shares	$ 62.7
Health Net, Inc.
Business Acquisition [Line Items]
Acquired finite-lived intangible assets, weighted average useful life			12 years
Business acquisition, consideration transferred, including assumed debt	$ 5,990
Business acquisition, consideration transferred, assumption of outstanding debt	703
Total consideration for acquisition transaction	5,287
Business acquisition, consideration transferred, common stock issued (in dollars per share)	3,038
Business acquisition, cash paid	2,247
Business acquisition, fair value adjustment, stock based compensation	$ 2
Business acquisition, shares converted ratio	0.622
Business acquisition,share price | $ / shares	$ 28.25
Business acquisition, common stock issued (in shares) | shares	48,449,444
Goodwill, period increase		$ 258
Health Net, Inc. | Selling, General and Administrative Expenses [Member]
Business Acquisition [Line Items]
Business acquisition, acquisition related expenses			$ 234

Health Net Merger Schedule of

Health Net Merger Schedule of Recognized Identifiable Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Mar. 24, 2016	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill	$ 4,712		$ 842	$ 754
Managed Care
Business Acquisition [Line Items]
Goodwill	3,689		361	276
Specialty Services
Business Acquisition [Line Items]
Goodwill	1,023		$ 481	$ 478
Health Net, Inc.
Business Acquisition [Line Items]
Cash and cash equivalents		$ 956
Premium and related receivables (a)		1,890
Short term investments		74
Other current assets		524
Long term investments		2,037
Restricted deposits		30
Property, software and equipment, net		41
Intangible assets (b)	1,530	1,530
Other long term assets		136
Total assets acquired		7,218
Medical claims liability (c)		1,482
Borrowings under revolving credit facility		285
Accounts payable and accrued expenses (c) (d)		2,297
Return of premium payable		435
Unearned revenue		130
Long term deferred tax liabilities (e)		311
Long term debt (f)		418
Other long term liabilities		432
Total liabilities assumed		5,790
Total identifiable net assets		1,428
Goodwill		3,859
Total assets acquired and liabilities assumed		5,287
Estimated fair value of risk corridor receivable	$ 9
Acquired finite-lived intangible assets, weighted average useful life	12 years
Finite-Lived Intangible Assets, Purchase Accounting Adjustments	$ 30
Substance abuse rehabilitation claims recorded in medical claims liability	160
Premium deficiency reserves	253
Deferred tax liabilities noncurrent, net	$ 365
Health Net, Inc. | Managed Care
Business Acquisition [Line Items]
Goodwill		3,317
Health Net, Inc. | Specialty Services
Business Acquisition [Line Items]
Goodwill		542
Health Net, Inc. | Senior notes
Business Acquisition [Line Items]
Long term debt (f)		418
Face amount of senior notes		400
Unamortized premium		$ 18

Health Net Merger Fair value of

Health Net Merger Fair value of Intangibles and weighted average (Details) - Health Net, Inc. $ in Millions	12 Months Ended
	Dec. 31, 2016USD ($)
Business Acquisition [Line Items]
Finite-lived intangible assets, purchase accounting adjustments increase in weighted average useful life	2 years
Acquired finite-lived intangible assets, weighted average useful life	12 years
Recognized identifiable intangible assets	$ 1,530
Purchased contract rights
Business Acquisition [Line Items]
Acquired finite-lived intangible assets, weighted average useful life	13 years
Recognized identifiable intangible assets	$ 1,095
Provider contracts
Business Acquisition [Line Items]
Acquired finite-lived intangible assets, weighted average useful life	11 years
Recognized identifiable intangible assets	$ 181
Trade names
Business Acquisition [Line Items]
Acquired finite-lived intangible assets, weighted average useful life	10 years
Recognized identifiable intangible assets	$ 150
Developed technology
Business Acquisition [Line Items]
Acquired finite-lived intangible assets, weighted average useful life	5 years
Recognized identifiable intangible assets	$ 104

Health Net Merger Restructuring

Health Net Merger Restructuring Related Charges (Details) - General and administrative expense $ in Millions	12 Months Ended
	Dec. 31, 2016USD ($)
Accrued Restructuring Cost [Roll Forward]
Total accrued restructuring costs as of beginning of period	$ 0
Charges incurred	89
Paid/settled	(71)
Total accrued restructuring costs as of end of period	18
Employee Termination Costs
Accrued Restructuring Cost [Roll Forward]
Total accrued restructuring costs as of beginning of period	0
Charges incurred	46
Paid/settled	(28)
Total accrued restructuring costs as of end of period	18
Expected employee termination cost	51
Stock Based Compensation
Accrued Restructuring Cost [Roll Forward]
Total accrued restructuring costs as of beginning of period	0
Charges incurred	43
Paid/settled	(43)
Total accrued restructuring costs as of end of period	0
Expected employee termination cost	$ 45

Health Net Merger Schedule of U

Health Net Merger Schedule of Unaudited Pro Forma Financial Information (Details) - Health Net, Inc. - USD ($) $ / shares in Units, $ in Millions	9 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Revenue of acquiree since acquisition date, actual	$ 13,454
Total revenues		$ 44,280	$ 38,826
Net earnings attributable to Centene Corporation			$ 245
Diluted earnings per share			$ 1.43

Health Net Merger Commitments (

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

Acquisitions and Noncontrolli63

Acquisitions and Noncontrolling Interest Acquisitions (Details) - USD ($) $ in Millions	1 Months Ended
	Sep. 30, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill		$ 4,712	$ 842	$ 754
Redeemable noncontrolling interests		145	156
Managed Care
Business Acquisition [Line Items]
Goodwill		$ 3,689	$ 361	$ 276
Managed Care | Agate Resources, Inc.
Business Acquisition [Line Items]
Acquisition consideration	$ 114
Business acquisition, cash paid	93
Business combination, consideration transfered, present value of future consideration	$ 12
Business combination, deferred payment, period of payments	3 years
Contingent liability	$ 9
Business combination, contingent consideration arrangement based on achievement of underwriting targets, duration of cash payment	3 years
Goodwill	$ 42
Recognized identifiable intangible assets	$ 39
Description of contingent consideration arrangements	A portion of the contingent consideration is based on the achievement of underwriting targets and is being paid in cash over a three year period; the remainder is based on the net proceeds of a retrospective rate adjustment, which was settled in 2016

Acquisitions and Noncontrolli64

Acquisitions and Noncontrolling Interest Non Controlling Interest (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Changes, Net [Abstract]
Earnings (loss) from continuing operations, net of income tax expense	$ 255	$ 148	$ 171	$ (15)	$ 112	$ 92	$ 88	$ 64	$ 559	$ 356	$ 268
Increase in equity for distributions from and consolidation of noncontrolling interest									2	11
Reclassification to redeemable noncontrolling interest									0	1	(9)
Net transfers from (to) noncontrolling interest									2	12	(9)
Changes from net earnings attributable to Centene Corporation and net transfers from (to) the noncontrolling interest									561	368	$ 259
Reconciliation of Changes in the Redeemable Noncontrolling Interest [Roll Forward]
Redeemable noncontrolling interest, beginning balance				$ 156					156
Noncontrolling interest related to TPG acquisition									3
Noncontrolling interest repurchased related to Celtic Insurance Company									(12)
Net losses attributable to noncontrolling interest									(2)
Redeemable noncontrolling interest, ending balance	$ 145				$ 156				$ 145	$ 156
Celtic Insurance Company
Noncontrolling Interest [Line Items]
Ownership percentage by parent	100.00%				75.00%				100.00%	75.00%	100.00%
Cenpatico Integrated Care
Noncontrolling Interest [Line Items]
Ownership percentage by parent	80.00%				80.00%				80.00%	80.00%	80.00%
Centurion
Noncontrolling Interest [Line Items]
Ownership percentage by parent	51.00%				51.00%				51.00%	51.00%	51.00%
Home State Health Plan
Noncontrolling Interest [Line Items]
Ownership percentage by parent	95.00%				95.00%				95.00%	95.00%	95.00%
The Practice (Group) Limited (TPG) (1)
Noncontrolling Interest [Line Items]
Ownership percentage by parent	75.00%				49.00%				75.00%	49.00%	49.00%
Payments to acquire interest in subsidiaries and affiliates									$ 8
U.S. Medical Management
Noncontrolling Interest [Line Items]
Ownership percentage by parent	68.00%				68.00%				68.00%	68.00%	68.00%
Non controlling Interest
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Changes, Net [Abstract]
Increase in equity for distributions from and consolidation of noncontrolling interest									$ 2	$ 11	$ 0
Reclassification to redeemable noncontrolling interest										$ 1	$ (9)

Short-Term And Long-Term Inve65

Short-Term And Long-Term Investments, Restricted Deposits (Short-Term And Long-Term Investments, Restricted Deposits) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Schedule Of Investments And Restricted Deposits By Type [Line Items]
Amortized Cost	$ 5,233	$ 2,225
Available For Sale Securities Gross Unrealized Gain Accumulated In Investments	15	5
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments	(60)	(12)
Fair Value	5,188	2,218
U.S. Treasury securities and obligations of U.S. government corporations and agencies
Schedule Of Investments And Restricted Deposits By Type [Line Items]
Amortized Cost	364	431
Available For Sale Securities Gross Unrealized Gain Accumulated In Investments	0	0
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments	(1)	(2)
Fair Value	363	429
Corporate securities
Schedule Of Investments And Restricted Deposits By Type [Line Items]
Amortized Cost	1,933	859
Available For Sale Securities Gross Unrealized Gain Accumulated In Investments	12	2
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments	(13)	(8)
Fair Value	1,932	853
Restricted certificates of deposit
Schedule Of Investments And Restricted Deposits By Type [Line Items]
Amortized Cost	5	5
Available For Sale Securities Gross Unrealized Gain Accumulated In Investments	0	0
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments	0	0
Fair Value	5	5
Restricted cash equivalents
Schedule Of Investments And Restricted Deposits By Type [Line Items]
Amortized Cost	6	78
Available For Sale Securities Gross Unrealized Gain Accumulated In Investments	0	0
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments	0	0
Fair Value	6	78
Municipal securities
Schedule Of Investments And Restricted Deposits By Type [Line Items]
Amortized Cost	1,767	496
Available For Sale Securities Gross Unrealized Gain Accumulated In Investments	1	2
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments	(35)	(1)
Fair Value	1,733	497
Asset backed securities
Schedule Of Investments And Restricted Deposits By Type [Line Items]
Amortized Cost	317	163
Available For Sale Securities Gross Unrealized Gain Accumulated In Investments	1	0
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments	(1)	(1)
Fair Value	317	162
Residential mortgage backed securities
Schedule Of Investments And Restricted Deposits By Type [Line Items]
Amortized Cost	219	66
Available For Sale Securities Gross Unrealized Gain Accumulated In Investments	1	1
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments	(5)	0
Fair Value	215	67
Commercial mortgage backed securities
Schedule Of Investments And Restricted Deposits By Type [Line Items]
Amortized Cost	343	40
Available For Sale Securities Gross Unrealized Gain Accumulated In Investments	0	0
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments	(5)	0
Fair Value	338	40
Cost and equity method investments
Schedule Of Investments And Restricted Deposits By Type [Line Items]
Amortized Cost	163	71
Available For Sale Securities Gross Unrealized Gain Accumulated In Investments	0	0
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments	0	0
Fair Value	163	71
Life insurance contracts
Schedule Of Investments And Restricted Deposits By Type [Line Items]
Amortized Cost	116	16
Available For Sale Securities Gross Unrealized Gain Accumulated In Investments	0	0
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments	0	0
Fair Value	$ 116	$ 16

Short-Term And Long-Term Inve66

Short-Term And Long-Term Investments, Restricted Deposits (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Jan. 31, 2016	Dec. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Percentage of Investment Grade Investments Rated by S&P or Moody's		95.00%
Investments Recorded At Fair Value That Carry Rating Of A A Plus, Weighted Average, Duration		3 years 8 months 12 days
Percentage of voting interests acquired	19.00%
Stock issued during period, shares, new issues	1,144,462
Stock Issued During Period, Value, Purchase of Assets	$ 68

Short-Term And Long-Term Inve67

Short-Term And Long-Term Investments And Restricted Deposits By Investment Type (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016USD ($)position	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)
Schedule of Available-for-sale Securities [Line Items]
Available for sale securities continuous unrealized loss position less than 12 months aggregate losses accumulated in investments	$ (59)	$ (10)
Less than 12 months, fair value	3,218	1,248
Available for sale securities continuous unrealized loss position 12 months or longer aggregate losses accumulated in investments	(1)	(2)
12 Months or More, fair value	$ 89	68
Positions from which gross unrealized losses were generated | position	1,881
Total number of positions | position	2,845
Income (loss) from equity method investments	$ 5	8	$ 6
U.S. Treasury securities and obligations of U.S. government corporations and agencies
Schedule of Available-for-sale Securities [Line Items]
Available for sale securities continuous unrealized loss position less than 12 months aggregate losses accumulated in investments	(1)	(2)
Less than 12 months, fair value	215	294
Available for sale securities continuous unrealized loss position 12 months or longer aggregate losses accumulated in investments	0	0
12 Months or More, fair value	2	14
Corporate securities
Schedule of Available-for-sale Securities [Line Items]
Available for sale securities continuous unrealized loss position less than 12 months aggregate losses accumulated in investments	(12)	(6)
Less than 12 months, fair value	1,020	561
Available for sale securities continuous unrealized loss position 12 months or longer aggregate losses accumulated in investments	(1)	(2)
12 Months or More, fair value	39	41
Municipal securities
Schedule of Available-for-sale Securities [Line Items]
Available for sale securities continuous unrealized loss position less than 12 months aggregate losses accumulated in investments	(35)	(1)
Less than 12 months, fair value	1,423	208
Available for sale securities continuous unrealized loss position 12 months or longer aggregate losses accumulated in investments	0	0
12 Months or More, fair value	30	5
Asset backed securities
Schedule of Available-for-sale Securities [Line Items]
Available for sale securities continuous unrealized loss position less than 12 months aggregate losses accumulated in investments	(1)	(1)
Less than 12 months, fair value	101	121
Available for sale securities continuous unrealized loss position 12 months or longer aggregate losses accumulated in investments	0	0
12 Months or More, fair value	18	8
Residential mortgage backed securities
Schedule of Available-for-sale Securities [Line Items]
Available for sale securities continuous unrealized loss position less than 12 months aggregate losses accumulated in investments	(5)	0
Less than 12 months, fair value	188	30
Available for sale securities continuous unrealized loss position 12 months or longer aggregate losses accumulated in investments	0	0
12 Months or More, fair value	0	0
Commercial mortgage backed securities
Schedule of Available-for-sale Securities [Line Items]
Available for sale securities continuous unrealized loss position less than 12 months aggregate losses accumulated in investments	(5)	0
Less than 12 months, fair value	271	34
Available for sale securities continuous unrealized loss position 12 months or longer aggregate losses accumulated in investments	0	0
12 Months or More, fair value	$ 0	$ 0

Contractual Maturities of Short

Contractual Maturities of Short-Term And Long-Term Investments And Restricted Deposits (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Investments
Schedule of Available-for-sale Securities [Line Items]
One year or less, Amortized Cost	$ 500	$ 176
One year through five years, Amortized Cost	1,982	1,662
Five years through ten years, Amortized Cost	1,101	267
Greater than ten years, Amortized Cost	633	5
Investments and restricted deposits contractual maturities, without single maturity date, net carrying amount	879	0
Total, Amortized Cost	5,095	2,110
One year or less, Fair Value	500	176
One year through five years, Fair Value	1,974	1,654
Five years through ten years, Fair Value	1,089	268
Greater than ten years, Fair Value	617	5
Investments and restricted deposits contractual maturities, without single maturity date, fair value	870	0
Total, Fair Value	5,050	2,103
Restricted Deposits
Schedule of Available-for-sale Securities [Line Items]
One year or less, Amortized Cost	91	93
One year through five years, Amortized Cost	47	22
Five years through ten years, Amortized Cost	0	0
Greater than ten years, Amortized Cost	0	0
Investments and restricted deposits contractual maturities, without single maturity date, net carrying amount	0	0
Total, Amortized Cost	138	115
One year or less, Fair Value	91	93
One year through five years, Fair Value	47	22
Five years through ten years, Fair Value	0	0
Greater than ten years, Fair Value	0	0
Investments and restricted deposits contractual maturities, without single maturity date, fair value	0	0
Total, Fair Value	$ 138	$ 115

Fair Value Measurements (Fair V

Fair Value Measurements (Fair Value Measurements By Level For Assets Measured At Fair Value On A Recurring Basis) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Cash and cash equivalents	$ 3,930	$ 1,760
U.S. Treasury securities and obligations of U.S. government corporations and agencies	236	397
Corporate securities	1,932	853
Municipal securities	1,733	497
Asset backed securities	317	162
Total investments	4,771	2,016
Cash and cash equivalents	6	78
Certificates of deposit	5	5
U.S. Treasury securities and obligations of U.S. government corporations and agencies	127	32
Total restricted deposits	138	115
Interest rate swap agreements	4	11
Total assets at fair value	8,843	3,902
Interest rate swap agreements	62	2
Total liabilities at fair value	62	2
Level I
Cash and cash equivalents	3,930	1,760
U.S. Treasury securities and obligations of U.S. government corporations and agencies	221	325
Corporate securities	0	0
Municipal securities	0	0
Asset backed securities	0	0
Total investments	221	325
Cash and cash equivalents	6	78
Certificates of deposit	5	5
U.S. Treasury securities and obligations of U.S. government corporations and agencies	127	32
Total restricted deposits	138	115
Interest rate swap agreements	0	0
Total assets at fair value	4,289	2,200
Interest rate swap agreements	0	0
Total liabilities at fair value	0	0
Level II
Cash and cash equivalents	0	0
U.S. Treasury securities and obligations of U.S. government corporations and agencies	15	72
Corporate securities	1,932	853
Municipal securities	1,733	497
Asset backed securities	317	162
Total investments	4,550	1,691
Cash and cash equivalents	0	0
Certificates of deposit	0	0
U.S. Treasury securities and obligations of U.S. government corporations and agencies	0	0
Total restricted deposits	0	0
Interest rate swap agreements	4	11
Total assets at fair value	4,554	1,702
Interest rate swap agreements	62	2
Total liabilities at fair value	62	2
Level III
Cash and cash equivalents	0	0
U.S. Treasury securities and obligations of U.S. government corporations and agencies	0	0
Corporate securities	0	0
Municipal securities	0	0
Asset backed securities	0	0
Total investments	0	0
Cash and cash equivalents	0	0
Certificates of deposit	0	0
U.S. Treasury securities and obligations of U.S. government corporations and agencies	0	0
Total restricted deposits	0	0
Interest rate swap agreements	0	0
Total assets at fair value	0	0
Interest rate swap agreements	0	0
Total liabilities at fair value	0	0
Residential mortgage backed securities
Residential mortgage backed securities	215	67
Commercial mortgage backed securities	215	67
Residential mortgage backed securities | Level I
Residential mortgage backed securities	0	0
Commercial mortgage backed securities	0	0
Residential mortgage backed securities | Level II
Residential mortgage backed securities	215	67
Commercial mortgage backed securities	215	67
Residential mortgage backed securities | Level III
Residential mortgage backed securities	0	0
Commercial mortgage backed securities	0	0
Commercial mortgage backed securities
Residential mortgage backed securities	338	40
Commercial mortgage backed securities	338	40
Commercial mortgage backed securities | Level I
Residential mortgage backed securities	0	0
Commercial mortgage backed securities	0	0
Commercial mortgage backed securities | Level II
Residential mortgage backed securities	338	40
Commercial mortgage backed securities	338	40
Commercial mortgage backed securities | Level III
Residential mortgage backed securities	0	0
Commercial mortgage backed securities	$ 0	$ 0

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Transfers from Level I to Level II	$ 1
Transfers from Level II to Level I	45
Life insurance contracts and cost-method investments	$ 279	$ 87

Property, Software And Equipm71

Property, Software And Equipment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Property, software and equipment, gross	$ 1,239	$ 869
Less accumulated depreciation	(442)	(351)
Property, software and equipment, net	797	518
Depreciation expense	101	78	$ 65
Land
Property, Plant and Equipment [Line Items]
Property, software and equipment, gross	113	104
Buildings
Property, Plant and Equipment [Line Items]
Property, software and equipment, gross	271	223
Computer Software
Property, Plant and Equipment [Line Items]
Property, software and equipment, gross	377	237
Computer Hardware
Property, Plant and Equipment [Line Items]
Property, software and equipment, gross	179	105
Furniture And Office Equipment
Property, Plant and Equipment [Line Items]
Property, software and equipment, gross	126	92
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, software and equipment, gross	173	108
Assets Held Under Capital Leases
Property, Plant and Equipment [Line Items]
Less accumulated depreciation	(4)	(4)
Property, software and equipment, net	$ 5	$ 6

Goodwill And Intangible Asset72

Goodwill And Intangible Assets (Schedule Of Changes In Goodwill By Operating Segment) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Goodwill [Roll Forward]
Goodwill, beginning	$ 842	$ 754
Acquisitions and purchase accounting adjustments	3,873	106
Impairment		(18)
Goodwill, ending	4,712	842
Goodwill, foreign currency translation gain (loss)	(3)
Managed Care
Goodwill [Roll Forward]
Goodwill, beginning	361	276
Acquisitions and purchase accounting adjustments	3,331	103
Impairment		(18)
Goodwill, ending	3,689	361
Goodwill, foreign currency translation gain (loss)	(3)
Specialty Services
Goodwill [Roll Forward]
Goodwill, beginning	481	478
Acquisitions and purchase accounting adjustments	542	3
Impairment		0
Goodwill, ending	1,023	$ 481
Goodwill, foreign currency translation gain (loss)	$ 0

Goodwill And Intangible Asset73

Goodwill And Intangible Assets (Schedule Of Intangible Assets) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 1,751	$ 217
Weighted average life in years	11 years 6 months	9 years 9 months 18 days
Total accumulated amortization	$ (206)	$ (62)
Intangible Assets, Net, Total	1,545	155
Amortization of acquired intangible assets	147	24	$ 16
Purchased contract rights
Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 1,171	$ 71
Weighted average life in years	12 years 7 months 6 days	8 years 9 months 18 days
Total accumulated amortization	$ (95)	$ (21)
Provider contracts
Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 285	$ 103
Weighted average life in years	10 years 8 months 12 days	11 years 1 month 6 days
Total accumulated amortization	$ (55)	$ (24)
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 22	$ 26
Weighted average life in years	8 years 2 months 12 days	8 years 1 month 6 days
Total accumulated amortization	$ (21)	$ (14)
Trade names
Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 163	$ 12
Weighted average life in years	9 years 7 months 6 days	7 years 3 months 18 days
Total accumulated amortization	$ (17)	$ (2)
Developed technology
Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 110	$ 5
Weighted average life in years	5 years	5 years
Total accumulated amortization	$ (18)	$ (1)

Goodwill And Intangible Asset74

Goodwill And Intangible Assets (Schedule Of Future Amortization Expenses) (Details) $ in Millions	Dec. 31, 2016USD ($)
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2,017	$ 155
2,018	152
2,019	152
2,020	150
2,021	$ 133

Medical Claims Liability Schedu

Medical Claims Liability Schedule of change In medical claims liability by operating segment(Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Jan. 01, 2014
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Medical claims liability	$ 3,929	$ 2,298	$ 1,723	$ 1,112
Acquisitions	1,482	79
Incurred related to: current year	30,946	17,471	12,820
Incurred related to: prior years	(310)	(229)	(142)
Total incurred	30,636	17,242	12,678
Paid related to: current year	28,532	15,279	11,122
Paid related to: prior years	1,960	1,467	945
Total paid	30,492	16,746	12,067
Balance , net	3,924
Reinsurance recoverable	(5)
Balance, December 31,	3,929	2,298	1,723	1,112
Medicaid Premium Revenue
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Incurred related to: prior years	39	47	26
Managed Care
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Medical claims liability	3,874	2,252	1,696	1,101
Acquisitions	1,482	79
Incurred related to: current year	30,073	16,974	12,468
Incurred related to: prior years	(303)	(223)	(141)
Total incurred	29,770	16,751	12,327
Paid related to: current year	27,714	14,826	10,796
Paid related to: prior years	1,921	1,448	936
Total paid	29,635	16,274	11,732
Balance , net	3,869
Reinsurance recoverable	(5)
Balance, December 31,	3,874	2,252	1,696	1,101
Specialty Services
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Medical claims liability	55	46	27	11
Acquisitions	0
Incurred related to: current year	873	497	352
Incurred related to: prior years	(7)	(6)	(1)
Total incurred	866	491	351
Paid related to: current year	818	453	326
Paid related to: prior years	39	19	9
Total paid	857	472	335
Balance , net	55
Reinsurance recoverable	0
Balance, December 31,	$ 55	$ 46	$ 27	$ 11

Medical Claims Liability Cumula

Medical Claims Liability Cumulative incurred and Paid Claims (Details) - Health insurance product line - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Claims Development [Line Items]
Consolidated total, net of reinsurance	$ 3,924
Managed Care
Claims Development [Line Items]
Short-duration insurance contracts, incurred claims and allocated claim adjustment expense, net	87,083
Short-duration insurance contracts, cumulative paid claims and allocated claim adjustment expense, net	83,214
Short-duration insurance contracts, liability for unpaid claims and allocated claim adjustment expense, net, not separately presented	3,869
Specialty Services
Claims Development [Line Items]
Short-duration insurance contracts, incurred claims and allocated claim adjustment expense, net	1,711
Short-duration insurance contracts, cumulative paid claims and allocated claim adjustment expense, net	1,656
Short-duration insurance contracts, liability for unpaid claims and allocated claim adjustment expense, net, not separately presented	55
Short-duration Insurance contracts, accident year 2014 | Managed Care
Claims Development [Line Items]
Short-duration insurance contracts, incurred claims and allocated claim adjustment expense, net	23,468	$ 23,472	$ 23,790
Short-duration insurance contracts, cumulative paid claims and allocated claim adjustment expense, net	23,450	22,895	20,415
Short-duration Insurance contracts, accident year 2014 | Specialty Services
Claims Development [Line Items]
Short-duration insurance contracts, incurred claims and allocated claim adjustment expense, net	346	348	352
Short-duration insurance contracts, cumulative paid claims and allocated claim adjustment expense, net	346	346	$ 326
Short-duration insurance contracts, accident year 2015 | Managed Care
Claims Development [Line Items]
Short-duration insurance contracts, incurred claims and allocated claim adjustment expense, net	29,833	30,122
Short-duration insurance contracts, cumulative paid claims and allocated claim adjustment expense, net	29,539	27,211
Short-duration insurance contracts, accident year 2015 | Specialty Services
Claims Development [Line Items]
Short-duration insurance contracts, incurred claims and allocated claim adjustment expense, net	492	497
Short-duration insurance contracts, cumulative paid claims and allocated claim adjustment expense, net	492	$ 453
Short-duration insurance contracts, accident year 2016 | Managed Care
Claims Development [Line Items]
Short-duration insurance contracts, incurred claims and allocated claim adjustment expense, net	33,782
Short-duration insurance contracts, cumulative paid claims and allocated claim adjustment expense, net	30,225
Short-duration insurance contracts, accident year 2016 | Specialty Services
Claims Development [Line Items]
Short-duration insurance contracts, incurred claims and allocated claim adjustment expense, net	873
Short-duration insurance contracts, cumulative paid claims and allocated claim adjustment expense, net	$ 818

Medical Claims Liability Incurr

Medical Claims Liability Incurred Claims and Allocated Claims Adjustment Expenses (Details) - Health insurance product line claim in Millions, $ in Millions	Dec. 31, 2016USD ($)claim	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)
Managed Care
Claims Development [Line Items]
Short-duration insurance contracts, incurred claims and allocated claim adjustment expense, net	$ 87,083
Specialty Services
Claims Development [Line Items]
Short-duration insurance contracts, incurred claims and allocated claim adjustment expense, net	1,711
Short-duration Insurance contracts, accident year 2014 | Managed Care
Claims Development [Line Items]
Short-duration insurance contracts, incurred claims and allocated claim adjustment expense, net	23,468	$ 23,472	$ 23,790
Short-duration insurance contracts, expected development on reported claims	$ 2
Short-duration Insurance Contracts, Number of Reported Claims | claim	121
Short-duration Insurance contracts, accident year 2014 | Specialty Services
Claims Development [Line Items]
Short-duration insurance contracts, incurred claims and allocated claim adjustment expense, net	$ 346	348	$ 352
Short-duration insurance contracts, expected development on reported claims	$ 0
Short-duration Insurance Contracts, Number of Reported Claims | claim	3
Short-duration insurance contracts, accident year 2015 | Managed Care
Claims Development [Line Items]
Short-duration insurance contracts, incurred claims and allocated claim adjustment expense, net	$ 29,833	30,122
Short-duration insurance contracts, expected development on reported claims	$ 52
Short-duration Insurance Contracts, Number of Reported Claims | claim	153
Short-duration insurance contracts, accident year 2015 | Specialty Services
Claims Development [Line Items]
Short-duration insurance contracts, incurred claims and allocated claim adjustment expense, net	$ 492	$ 497
Short-duration insurance contracts, expected development on reported claims	$ 0
Short-duration Insurance Contracts, Number of Reported Claims | claim	3
Short-duration insurance contracts, accident year 2016 | Managed Care
Claims Development [Line Items]
Short-duration insurance contracts, incurred claims and allocated claim adjustment expense, net	$ 33,782
Short-duration insurance contracts, expected development on reported claims	$ 3,001
Short-duration Insurance Contracts, Number of Reported Claims | claim	165
Short-duration insurance contracts, accident year 2016 | Specialty Services
Claims Development [Line Items]
Short-duration insurance contracts, incurred claims and allocated claim adjustment expense, net	$ 873
Short-duration insurance contracts, expected development on reported claims	$ 49
Short-duration Insurance Contracts, Number of Reported Claims | claim	6

Affordable Care Act (Details)

Affordable Care Act (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Sep. 30, 2016	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015
Affordable Care Act [Abstract]
Affordable Care Act risk adjustment and reinsurance, pre-tax benefit, period increase (decrease)	$ (19)	$ 70	$ 51
Risk adjustment			(425)	$ (108)
Reinsurance			122	24
Risk corridor			(3)	(4)
Minimum MLR			(18)	(15)
Cost sharing reductions			$ (147)	$ (40)

Debt (Schedule Of Debt) (Detail

Debt (Schedule Of Debt) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Nov. 30, 2016	Jun. 30, 2016	Feb. 29, 2016	Dec. 31, 2015	Apr. 30, 2014
Debt Instrument [Line Items]
Fair value of interest rate swap agreements	$ (58,000,000)				$ 9,000,000
Senior notes, Total	4,550,000,000				937,000,000
Revolving credit agreement	100,000,000
Mortgage notes payable	64,000,000				67,000,000
Capital lease obligations and other	18,000,000				6,000,000
Debt issuance costs	(77,000,000)				(14,000,000)
Total debt	4,655,000,000				1,221,000,000
Less current portion	(4,000,000)				(5,000,000)
Long term debt	4,651,000,000				1,216,000,000
Revolving credit agreement
Debt Instrument [Line Items]
Revolving credit agreement	100,000,000				225,000,000
$425 million 5.75% Senior notes, due June 1, 2017
Debt Instrument [Line Items]
Senior notes	$ 425,000,000
Interest rate stated, percentage	5.75%
Maturity date	Jun. 1, 2017
$1,400 million 5.625% Senior notes, due February 15, 2021
Debt Instrument [Line Items]
Senior notes	$ 1,400,000,000
Interest rate stated, percentage	5.625%
Maturity date	Feb. 15, 2021
$1,000 million 4.75% Senior notes, due May 15, 2022
Debt Instrument [Line Items]
Senior notes	$ 1,000,000,000
Interest rate stated, percentage	4.75%
Maturity date	May 15, 2022
$1,000 million 6.125% Senior notes, due February 15, 2024
Debt Instrument [Line Items]
Senior notes	$ 1,000,000,000
Interest rate stated, percentage	6.125%
Maturity date	Feb. 15, 2024
Four Point Seven Five Percent Senior Notes, due in twenty twenty five
Debt Instrument [Line Items]
Senior notes	$ 1,200,000,000
Interest rate stated, percentage	4.75%
Maturity date	Jan. 15, 2025
Senior notes
Debt Instrument [Line Items]
Senior notes	$ 400,000,000
Senior notes | $425 million 5.75% Senior notes, due June 1, 2017
Debt Instrument [Line Items]
Senior notes	0				428,000,000
Senior notes		$ 425,000,000
Interest rate stated, percentage		5.75%
Senior notes | $1,400 million 5.625% Senior notes, due February 15, 2021
Debt Instrument [Line Items]
Senior notes	1,400,000,000				0
Senior notes				$ 1,400,000,000
Interest rate stated, percentage				5.625%
Senior notes | $1,000 million 4.75% Senior notes, due May 15, 2022
Debt Instrument [Line Items]
Senior notes	1,008,000,000				500,000,000
Senior notes						$ 500,000,000
Interest rate stated, percentage			4.75%			4.75%
Senior notes | $1,000 million 6.125% Senior notes, due February 15, 2024
Debt Instrument [Line Items]
Senior notes	1,000,000,000				0
Senior notes				$ 1,000,000,000
Interest rate stated, percentage				6.125%
Senior notes | 4.75% Senior notes, due in 2025
Debt Instrument [Line Items]
Senior notes	$ 1,200,000,000				$ 0
Senior notes | Four Point Seven Five Percent Senior Notes, due in twenty twenty five
Debt Instrument [Line Items]
Senior notes		$ 1,200,000,000
Interest rate stated, percentage		4.75%

Debt (Narrative) (Details)

Debt (Narrative) (Details) € in Millions	Dec. 31, 2016USD ($)	Mar. 24, 2016USD ($)	Dec. 31, 2016USD ($)	Nov. 30, 2016USD ($)	Jun. 30, 2016USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2016EUR (€)	Mar. 31, 2016USD ($)	Mar. 23, 2016USD ($)	Feb. 29, 2016USD ($)	Dec. 31, 2015USD ($)	Jan. 31, 2015USD ($)	Apr. 30, 2014USD ($)
Debt Instrument [Line Items]
Derivative, notional amount												$ 200,000,000
Revolving credit agreement	$ 100,000,000		$ 100,000,000			$ 100,000,000
Mortgage notes payable	64,000,000		64,000,000			64,000,000					$ 67,000,000
$1,000 million 4.75% Senior notes, due May 15, 2022
Debt Instrument [Line Items]
Interest rate stated, percentage												4.75%	4.75%
Senior notes, at par												$ 200,000,000	$ 300,000,000
Senior notes
Debt Instrument [Line Items]
Senior notes	400,000,000		400,000,000			400,000,000
Non-recourse mortgage note due January 1, 2021
Debt Instrument [Line Items]
Mortgage notes payable	64,000,000		64,000,000			$ 64,000,000
Maturity date						Jan. 1, 2021
Mortgage note non-recourse interest rate						5.14%
Net book value of collateralized properties	173,000,000		173,000,000			$ 173,000,000
Revolving credit agreement
Debt Instrument [Line Items]
Revolving credit facility, maximum borrowing capacity								$ 1,000,000,000	$ 500,000,000
Revolving credit facility, due date						Mar. 24, 2021
Revolving credit agreement	$ 100,000,000		$ 100,000,000			$ 100,000,000					$ 225,000,000
Weighted average interest rate of outstanding borrowings	4.50%		4.50%			4.50%	4.50%
Line of credit covenant terms, ratio of debt to EBITDA, current year	3.5
Line of credit, covenant terms, ratio of debt to EBITA, after current year	3
Letter of Credit
Debt Instrument [Line Items]
Weighted average interest rate of outstanding borrowings	1.42%		1.42%			1.42%	1.42%
Outstanding balance	$ 71,000,000		$ 71,000,000			$ 71,000,000
Letter of Credit | Ribera Salud
Debt Instrument [Line Items]
Revolving credit agreement	$ 45,000,000		$ 45,000,000			$ 45,000,000	€ 42
$200 Million interest rate swap
Debt Instrument [Line Items]
Variable rate of swap, percentage	2.88%		2.88%			2.88%	2.88%
$425 million 5.75% Senior notes, due June 1, 2017
Debt Instrument [Line Items]
Senior notes	$ 425,000,000		$ 425,000,000			$ 425,000,000
Interest rate stated, percentage	5.75%		5.75%			5.75%	5.75%
Maturity date						Jun. 1, 2017
$425 million 5.75% Senior notes, due June 1, 2017 | Senior notes
Debt Instrument [Line Items]
Senior notes				$ 425,000,000
Interest rate stated, percentage				5.75%
Repayment of senior note and premium for early redemption				$ 447,000,000
Loss on extinguishment of debt				10,000,000
5.625% Senior notes, due in 2021
Debt Instrument [Line Items]
Senior notes	$ 1,400,000,000		$ 1,400,000,000			$ 1,400,000,000
Interest rate stated, percentage	5.625%		5.625%			5.625%	5.625%
Maturity date						Feb. 15, 2021
5.625% Senior notes, due in 2021 | Senior notes
Debt Instrument [Line Items]
Senior notes										$ 1,400,000,000
Interest rate stated, percentage										5.625%
$1,000 million 4.75% Senior notes, due May 15, 2022
Debt Instrument [Line Items]
Senior notes	$ 1,000,000,000		$ 1,000,000,000			$ 1,000,000,000
Interest rate stated, percentage	4.75%		4.75%			4.75%	4.75%
Maturity date						May 15, 2022
$1,000 million 4.75% Senior notes, due May 15, 2022 | Senior notes
Debt Instrument [Line Items]
Senior notes													$ 500,000,000
Interest rate stated, percentage					4.75%								4.75%
Proceeds from issuance of debt					$ 500,000,000
Senior notes, effective yield					4.41%
6.125% Senior notes, due in 2024
Debt Instrument [Line Items]
Senior notes	$ 1,000,000,000		$ 1,000,000,000			$ 1,000,000,000
Interest rate stated, percentage	6.125%		6.125%			6.125%	6.125%
Maturity date						Feb. 15, 2024
6.125% Senior notes, due in 2024 | Senior notes
Debt Instrument [Line Items]
Senior notes										$ 1,000,000,000
Interest rate stated, percentage										6.125%
Four Point Seven Five Percent Senior Notes, due in twenty twenty five
Debt Instrument [Line Items]
Senior notes	$ 1,200,000,000		$ 1,200,000,000			$ 1,200,000,000
Interest rate stated, percentage	4.75%		4.75%			4.75%	4.75%
Maturity date						Jan. 15, 2025
Four Point Seven Five Percent Senior Notes, due in twenty twenty five | Senior notes
Debt Instrument [Line Items]
Senior notes				$ 1,200,000,000
Interest rate stated, percentage				4.75%
6.375% Senior notes due in 2017 | Senior notes
Debt Instrument [Line Items]
Senior notes	$ 400,000,000	$ 400,000,000	$ 400,000,000			$ 400,000,000
Interest rate stated, percentage	6.375%	6.375%	6.375%			6.375%	6.375%
Repayment of senior note and premium for early redemption			$ 411,000,000
Loss on extinguishment of debt			3,000,000
Health Net, Inc.
Debt Instrument [Line Items]
Long term debt (f)		$ 418,000,000
Health Net, Inc. | Senior notes
Debt Instrument [Line Items]
Long term debt (f)		418,000,000
Line of Credit | Revolving credit agreement
Debt Instrument [Line Items]
Extinguishment of debt		$ 285,000,000
Surety Bond
Debt Instrument [Line Items]
Surety Bonds	$ 365,000,000		365,000,000			$ 365,000,000
Interest rate swap
Debt Instrument [Line Items]
Derivative, notional amount	$ 2,100,000,000		$ 2,100,000,000			$ 2,100,000,000
Variable rate of swap, percentage	3.92%		3.92%			3.92%	3.92%
Interest rate swap | $425 million 5.75% Senior notes, due June 1, 2017 | Senior notes
Debt Instrument [Line Items]
Gain (loss) on contract termination				$ 2,000,000
Derivative, notional amount				$ 250,000,000

Debt Interest Rate Swaps (Detai

Debt Interest Rate Swaps (Details) - USD ($)	Dec. 31, 2016	Nov. 30, 2016	Feb. 29, 2016	Dec. 31, 2015	Jan. 31, 2015
Debt Instrument [Line Items]
Derivative, notional amount					$ 200,000,000
Interest rate swap agreements	$ 4,000,000			$ 11,000,000
Interest rate swap agreements	62,000,000			$ 2,000,000
Interest rate swap
Debt Instrument [Line Items]
Derivative, notional amount	$ 2,100,000,000
Swap average, variable interest rate	3.92%
weighted average interest rate, interest rate swap agreements	4.83%
February 15, 2021 Expiration, interest rate swap
Debt Instrument [Line Items]
Derivative, notional amount	$ 600,000,000		$ 600,000,000
Swap average, variable interest rate			4.22%
May 15, 2022 Expiration, interest rate swap
Debt Instrument [Line Items]
Derivative, notional amount	500,000,000
February 15, 2024, Interest rate swap
Debt Instrument [Line Items]
Derivative, notional amount	$ 1,000,000,000		$ 1,000,000,000
Swap average, variable interest rate			4.44%
Five Point Seven Five Percent Senior Notes, Due June first twenty seventeen | Senior notes | Interest rate swap
Debt Instrument [Line Items]
Derivative, notional amount		$ 250,000,000

Debt (Schedule Of Aggregate Mat

Debt (Schedule Of Aggregate Maturities Of Debt) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Debt Disclosure [Abstract]
2,017	$ 4
2,018	4
2,019	16
2,020	4
2,021	1,404
Thereafter	3,350
Total	4,782
Fair Value of Outstanding Debt	$ 4,676	$ 1,239

Stockholders' Equity (Details)

Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Millions	Mar. 24, 2016	Jan. 31, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Class of Stock [Line Items]
Preferred stock, shares authorized			10,000,000	10,000,000
Preferred stock, par value (in usd per share)			$ 0.001	$ 0.001
Preferred stock, shares outstanding			0	0
Common stock, shares authorized to repurchase			8,000,000
Remaining number of shares available to be repurchased			3,335,448
Treasury stock, shares, acquired			1,078,335	918,628
Payments for repurchase of common stock (in usd)			$ 63	$ 53	$ 29
Percentage of voting interests acquired		19.00%
Stock issued during period, shares, new issues		1,144,462
Health Net, Inc.
Class of Stock [Line Items]
Business acquisition, common stock issued (in shares)	48,449,444
Business acquisition, consideration transferred, Centene common stock issued (in dollars per share)	$ 3,038

Statutory Capital Requirement84

Statutory Capital Requirements And Dividend Restrictions (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Statutory Capital Requirements And Dividend Restrictions [Abstract]
Statutory capital and surplus	$ 4,529	$ 2,284
Required minimum aggregate statutory capital and surplus	$ 2,259	$ 1,195

Income Taxes (Consolidated Inco

Income Taxes (Consolidated Income Tax Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Federal	$ 485	$ 332	$ 225
State and local	22	26	13
Total current provision	507	358	238
Deferred provision	92	(19)	(42)
Income tax expense	$ 599	$ 339	$ 196

Income Taxes (Reconciliation Of

Income Taxes (Reconciliation Of The Tax Provision At The U.S. Federal Statutory Rate To The Provision For Income Taxes) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Earnings from continuing operations, before income tax expense	$ 1,157	$ 697	$ 457
(Earnings) loss attributable to flow through noncontrolling interest	(8)	1	4
Earnings from continuing operations, less noncontrolling interest, before income tax expense	1,149	698	461
Tax provision at the U.S. federal statutory rate	402	244	162
State income taxes, net of federal income tax benefit	10	15	6
Nondeductible compensation	23	2	(13)
ACA Health Insurer Fee	162	75	44
Other, net	2	3	(3)
Income tax expense	$ 599	$ 339	$ 196

Income Taxes (Tax Effects Of Te

Income Taxes (Tax Effects Of Temporary Differences Which Give Rise To Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Medical claims liability	$ 66	$ 27
Nondeductible liabilities	39	14
Net operating loss and tax credit carryforwards	101	22
Compensation accruals	156	73
Acquisition costs	0	10
Premium and related receivables	79	36
Other	14	9
Deferred tax assets	455	191
Valuation allowance	(86)	(11)
Net deferred tax assets	369	180
Intangible assets	577	46
Prepaid assets	17	8
Fixed assets and intangibles	65	31
Investments in joint ventures	11	6
Other	2	2
Deferred tax liabilities	672	93
Deferred tax liabilities, net	$ (303)
Net deferred tax assets (liabilities)		$ 87

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating Loss Carryforwards [Line Items]
Increase in valuation allowance	$ (75)
Unrecognized tax benefits, increase resulting from acquisition	93	$ 0
Unrecognized tax benefits that would impact effective tax rate	87
Decrease in unrecognized tax benefits is reasonably possible	5
Net interest expense and penalties related to uncertain tax positionse	1
Accrued interest and penalties for uncertain tax position	5	1
Tax benefit related to 2013			$ 14
Undistributed earnings from non-US subsidiaries	$ 12	$ 8
Minimum
Operating Loss Carryforwards [Line Items]
Federal net operating losses expire period	2,020
State net operatinglosses expire period	2,017
Maximum
Operating Loss Carryforwards [Line Items]
Federal net operating losses expire period	2,036
State net operatinglosses expire period	2,036
UNITED STATES
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 59
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 37

Income Taxes Schedule of Compon

Income Taxes Schedule of Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Gross increases:
Gross unrecognized tax benefits, beginning of period	$ 5	$ 4
Current year tax positions	6	1
Acquired reserves	93	0
Gross decreases:
Prior year tax positions	(1)	0
Statute of limitation lapses	(1)	0
Gross unrecognized tax benefits, end of period	$ 102	$ 5

Stock Incentive Plans (Narrativ

Stock Incentive Plans (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Length of time options exercisable, years	10 years
Shares available for future awards	6,224,268
Allocated share-based compensation expense	$ 148	$ 71	$ 48
Income tax benefit recognized	67	24	17
Fair value of restricted stock and restricted stock units	147	$ 112	$ 82
Unrecognized compensation cost related to non-vested share	$ 233
Weighted-average period	2 years 5 months
Employee stock purchase plan issued	118,293	86,819	76,088
Stock Options | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vesting period, years	3 years
Stock Options | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vesting period, years	5 years
Restricted Stock Units Awards | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vesting period, years	1 year
Restricted Stock Units Awards | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vesting period, years	10 years
Health Net, Inc.
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future awards	5,376,101

Stock Incentive Plans (Summary

Stock Incentive Plans (Summary Of Stock Option Activity) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015		Dec. 31, 2014	[1]
Options Outstanding [Roll Forward]
Outstanding as of December 31, 2015 (in shares)	677,408
Shares granted	40,000	0	[1]	0
Shares exercised	(397,040)
Shares forfeited	0
Outstanding as of December 31, 2016 (in shares)	320,368	677,408
Exercisable as of December 31, 2016 (in shares)	280,368
Weighted Average Exercise Price Outstanding as of December 31, 2015 (usd per share)	$ 11.88
Weighted Average Exercise Price Granted (usd per share)	59.94
Weighted Average Exercise Price Exercised (usd per share)	12.25
Weighted Average Exercise Price Forfeited (usd per share)	0
Weighted Average Exercise Price Outstanding as of December 31, 2016 (usd per share)	17.44	$ 11.88
Weighted Average Exercise Price Exercisable as of December 31, 2016 (usd per share)	$ 11.37
Aggregate Intrinsic Value Outstanding as of December 31, 2016	$ 13
Aggregate Intrinsic Value Exercisable as of December 31, 2016	$ 13
Weighted Average Remaining Contractual Term Outstanding as of December 31, 2016	2 years 11 months
Weighted Average Remaining Contractual Term Exercisable as of December 31, 2016	1 year 11 months
[1]	(1) No options were awarded in the years ended December 31, 2015 and 2014.

Stock Incentive Plans (Option P

Stock Incentive Plans (Option Pricing Assumptions) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	[1]	Dec. 31, 2014	[1]
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Expected life (in years)	4 years 9 months	0 years		0 years
Risk-free interest rate	1.60%	0.00%		0.00%
Expected volatility	39.00%	0.00%		0.00%
Expected dividend yield	0.00%	0.00%		0.00%
No options awarded	40,000	0		0
Weighted-average fair value of options granted (usd per share)	$ 59.94	$ 0		$ 0
[1]	(1) No options were awarded in the years ended December 31, 2015 and 2014.

Stock Incentive Plans (Schedule

Stock Incentive Plans (Schedule Of Other Information Pertaining To Option Activity) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	[1]	Dec. 31, 2014	[1]
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Weighted-average fair value of options granted (usd per share)	$ 59.94	$ 0		$ 0
Total intrinsic value of stock options exercised	$ 19	$ 28		$ 17
Shares granted	40,000	0		0
[1]	(1) No options were awarded in the years ended December 31, 2015 and 2014.

Stock Incentive Plans (Non-Vest

Stock Incentive Plans (Non-Vested Restricted Stock And Restricted Stock) (Details)	12 Months Ended
	Dec. 31, 2016$ / sharesshares
Summary of non-vested restricted stock and restricted unit shares[Roll Forward]
Non-vested balance as of December 31, 2015 | shares	4,122,003
Shares Granted | shares	2,120,101
Shares Converted (1) | shares	1,285,674	[1]
Shares Vested | shares	(2,546,543)
Shares Forfeited | shares	(190,894)
Non-vested balance as of December 31, 2016 | shares	4,790,341
Weighted Average Grant Date Fair Value, Non-vested balance as of December 31, 2015 (usd per share) | $ / shares	$ 48.65
Weighted Average Grant Date Fair Value, Granted (usd per share) | $ / shares	57.71
Weighted Average Grant Date Fair Value, Converted (usd per share) | $ / shares	62.70	[1]
Weighted Average Grant Date Fair Value, Vested (usd per share) | $ / shares	50
Weighted Average Grant Date Fair Value, Forfeited (usd per share) | $ / shares	47.65
Weighted Average Grant Date Fair Value, Non-vested balance as of December 31, 2016 (usd per share) | $ / shares	$ 55.75
[1]	Health Net awards converted in connection with the acquisition.

Retirement Plan (Details)

Retirement Plan (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Contribution Pension and Other Postretirement Plans Disclosure [Abstract]
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 37	$ 19	$ 12

Commitments (Details)

Commitments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Loss Contingencies [Line Items]
Rent expense	$ 137	$ 64	$ 46
2,017	128
2,018	117
2,019	105
2,020	92
2,021	75
Thereafter	114
Annual non-cancelable minimum lease payments, Total	$ 631

Contingencies (Details)

Contingencies (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016USD ($)
Loss Contingencies [Line Items]
Kentucky Spirit Performance Bond	$ 25
Commonwealth of Kentucky, Expenditures due to Kentucky Spirit's Departure | Minimum
Loss Contingencies [Line Items]
Loss Contingency, Damages Sought, Value	28
Commonwealth of Kentucky, Expenditures due to Kentucky Spirit's Departure | Maximum
Loss Contingencies [Line Items]
Loss Contingency, Damages Sought, Value	40
Commonwealth of Kentucky, CMS Expenditures | Minimum
Loss Contingencies [Line Items]
Loss Contingency, Damages Sought, Value	92
Commonwealth of Kentucky, CMS Expenditures | Maximum
Loss Contingencies [Line Items]
Loss Contingency, Damages Sought, Value	$ 134

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Earnings Per Share [Abstract]
Earnings from continuing operations, net of tax	$ 255	$ 148	$ 171	$ (15)	$ 112	$ 92	$ 88	$ 64	$ 559	$ 356	$ 268
Discontinued operations, net of tax	6	(1)	(1)	(1)	(1)	1	0	(1)	3	(1)	3
Net earnings	$ 261	$ 147	$ 170	$ (16)	$ 111	$ 93	$ 88	$ 63	$ 562	$ 355	$ 271
Weighted average number of common shares outstanding	171,143,624	170,774,587	170,558,778	125,543,076					159,567,607	119,100,744	116,345,764
Common stock equivalents (as determined by applying the treasury stock method)									4,407,800	3,965,626	4,014,448
Weighted average number of common shares and potential dilutive common shares outstanding	175,511,179	175,495,339	174,848,996	125,543,076					163,975,407	123,066,370	120,360,212
Continuing operations (in usd per share)	$ 1.49	$ 0.87	$ 1	$ (0.12)	$ 0.94	$ 0.77	$ 0.74	$ 0.54	$ 3.50	$ 2.99	$ 2.30
Discontinued operations	0.04	(0.01)	0	(0.01)	(0.01)	0.01	0	(0.01)	0.02	(0.01)	0.03
Basic earnings per common share	1.53	0.86	1	(0.13)	0.93	0.78	0.74	0.53	3.52	2.98	2.33
Continuing operations	1.45	0.84	0.98	(0.12)	0.91	0.75	0.72	0.52	3.41	2.89	2.23
Discontinued operations	0.04	0	(0.01)	(0.01)	(0.01)	0.01	0	(0.01)	0.02	(0.01)	0.02
Diluted earnings per common share	$ 1.49	$ 0.84	$ 0.97	$ (0.13)	$ 0.90	$ 0.76	$ 0.72	$ 0.51	$ 3.43	$ 2.88	$ 2.25
Anti-dilutive stock options, restricted stock and restricted stock units excluded from the calculation of diluted earnings per common share									126,212	7,247	207,980

Segment Information (Details)

Segment Information (Details) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2016USD ($)	Sep. 30, 2016USD ($)	Jun. 30, 2016USD ($)	Mar. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Sep. 30, 2015USD ($)	Jun. 30, 2015USD ($)	Mar. 31, 2015USD ($)	Dec. 31, 2016USD ($)segment	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)
Segment Reporting [Abstract]
Number of Operating Segments | segment									2
Revenues	$ 11,911	$ 10,846	$ 10,897	$ 6,953	$ 6,302	$ 5,821	$ 5,506	$ 5,131	$ 40,607	$ 22,760	$ 16,560
Earnings from operations									1,260	705	464
Total assets	20,197				7,339				20,197	7,339	5,824
Managed Care
Revenues									37,523	20,544	14,775
Specialty Services
Revenues									3,084	2,216	1,785
Operating Segments | Managed Care
Revenues									37,722	20,644	14,835
Earnings from operations									1,070	513	353
Total assets	17,962				6,202				17,962	6,202	4,706
Operating Segments | Specialty Services
Revenues									9,037	7,080	4,804
Earnings from operations									190	192	111
Total assets	2,235				1,137				2,235	1,137	1,118
Intersegment Eliminations
Revenues									(6,152)	(4,964)	(3,079)
Earnings from operations									0	0	0
Total assets	$ 0				$ 0				0	0	0
Intersegment Eliminations | Managed Care
Revenues									199	100	60
Intersegment Eliminations | Specialty Services
Revenues									$ 5,953	$ 4,864	$ 3,019

Quarterly Selected Financial100

Quarterly Selected Financial Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Total revenues	$ 11,911	$ 10,846	$ 10,897	$ 6,953	$ 6,302	$ 5,821	$ 5,506	$ 5,131	$ 40,607	$ 22,760	$ 16,560
Earnings (loss) from continuing operations, net of income tax expense	255	148	171	(15)	112	92	88	64	559	356	268
Discontinued operations, net of tax	6	(1)	(1)	(1)	(1)	1	0	(1)	3	(1)	3
Net earnings	$ 261	$ 147	$ 170	$ (16)	$ 111	$ 93	$ 88	$ 63	$ 562	$ 355	$ 271
Continuing operations (in usd per share)	$ 1.49	$ 0.87	$ 1	$ (0.12)	$ 0.94	$ 0.77	$ 0.74	$ 0.54	$ 3.50	$ 2.99	$ 2.30
Discontinued operations	0.04	(0.01)	0	(0.01)	(0.01)	0.01	0	(0.01)	0.02	(0.01)	0.03
Basic earnings per common share	1.53	0.86	1	(0.13)	0.93	0.78	0.74	0.53	3.52	2.98	2.33
Continuing operations	1.45	0.84	0.98	(0.12)	0.91	0.75	0.72	0.52	3.41	2.89	2.23
Discontinued operations	0.04	0	(0.01)	(0.01)	(0.01)	0.01	0	(0.01)	0.02	(0.01)	0.02
Diluted earnings per common share	$ 1.49	$ 0.84	$ 0.97	$ (0.13)	$ 0.90	$ 0.76	$ 0.72	$ 0.51	$ 3.43	$ 2.88	$ 2.25
Basic (in shares)	171,143,624	170,774,587	170,558,778	125,543,076					159,567,607	119,100,744	116,345,764
Diluted (in shares)	175,511,179	175,495,339	174,848,996	125,543,076					163,975,407	123,066,370	120,360,212

Condensed Financial Informat101

Condensed Financial Information Of Registrant (Condensed Balance Sheets) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash and cash equivalents	$ 3,930	$ 1,760
Short term investments	505	176
Other current assets	832	390
Total current assets	8,365	3,605
Long term investments	4,545	1,927
Other long term assets	95	177
Total assets	20,197	7,339	$ 5,824
Current liabilities	8,623	3,629
Long term debt	4,651	1,216
Other long term liabilities	869	170
Total liabilities	14,143	5,015
Redeemable noncontrolling interests	145	156
Preferred Stock, Value, Issued	0	0
Common stock, $.001 par value; authorized 400,000,000 shares; 178,134,306 issued and 171,919,071 outstanding at December 31, 2016, and 126,855,477 issued and 120,342,981 outstanding at December 31, 2015	0	0
Additional paid-in capital	4,190	956
Accumulated other comprehensive loss	(36)	(10)
Retained earnings	1,920	1,358
Treasury stock, at cost (6,215,235 and 6,512,496 shares, respectively)	(179)	(147)
Total Centene stockholders’ equity	5,895	2,157
Noncontrolling interest	14	11
Total stockholders’ equity	5,909	2,168	$ 1,743	$ 1,243
Total liabilities and stockholders’ equity	20,197	7,339
Parent Company
Cash and cash equivalents	5	4
Short term investments	1	5
Other current assets	29	25
Total current assets	35	34
Long term investments	19	6
Investment in subsidiaries	10,674	3,435
Other long term assets	52	35
Total assets	10,780	3,510
Current liabilities	78	13
Long term debt	4,573	1,147
Other long term liabilities	75	26
Total liabilities	4,726	1,186
Redeemable noncontrolling interests	145	156
Preferred Stock, Value, Issued	0	0
Common stock, $.001 par value; authorized 400,000,000 shares; 178,134,306 issued and 171,919,071 outstanding at December 31, 2016, and 126,855,477 issued and 120,342,981 outstanding at December 31, 2015	0	0
Additional paid-in capital	4,190	956
Accumulated other comprehensive loss	(36)	(10)
Retained earnings	1,920	1,358
Treasury stock, at cost (6,215,235 and 6,512,496 shares, respectively)	(179)	(147)
Total Centene stockholders’ equity	5,895	2,157
Noncontrolling interest	14	11
Total stockholders’ equity	5,909	2,168
Total liabilities and stockholders’ equity	$ 10,780	$ 3,510

Condensed Financial Informat102

Condensed Financial Information Of Registrant Condensed Balance Sheets Other (Details) - USD ($) $ / shares in Units, $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Preferred stock, par value (in usd per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	400,000,000	400,000,000
Common stock, shares issued	178,134,306	126,855,477
Common stock, shares outstanding	171,919,071	120,342,981
Treasury stock, shares	6,215,235	6,512,496
Parent Company
Short term investments, amortized cost	$ 1	$ 5
Long term investments, amortized cost	$ 19	$ 6
Preferred stock, par value (in usd per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	400,000,000	400,000,000
Common stock, shares issued	178,134,306	126,855,477
Common stock, shares outstanding	171,919,071	120,342,981
Treasury stock, shares	6,215,235	6,512,496

Condensed Financial Informat103

Condensed Financial Information Of Registrant (Condensed Statements Of Operations) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Selling, general and administrative expenses									$ 3,676	$ 1,802	$ 1,298
Gain on contingent consideration									5	44	0
Investment and other income									114	35	28
Interest expense									(217)	(43)	(35)
Earnings (loss) before income taxes									1,157	697	457
Income tax benefit									599	339	196
Income (loss) from equity method investments									5	8	6
Net earnings									561	357	264
(Earnings) loss attributable to noncontrolling interests									1	(2)	7
Net earnings attributable to Centene	$ 255	$ 148	$ 171	$ (15)	$ 112	$ 92	$ 88	$ 64	$ 559	$ 356	$ 268
Basic earnings per common share (in usd per share)	$ 1.53	$ 0.86	$ 1	$ (0.13)	$ 0.93	$ 0.78	$ 0.74	$ 0.53	$ 3.52	$ 2.98	$ 2.33
Diluted earnings per common share (in usd per share)	$ 1.49	$ 0.84	$ 0.97	$ (0.13)	$ 0.90	$ 0.76	$ 0.72	$ 0.51	$ 3.43	$ 2.88	$ 2.25
Basic (in shares)	171,143,624	170,774,587	170,558,778	125,543,076					159,567,607	119,100,744	116,345,764
Diluted (in shares)	175,511,179	175,495,339	174,848,996	125,543,076					163,975,407	123,066,370	120,360,212
Parent Company
Selling, general and administrative expenses									$ 10	$ 9	$ 3
Gain on contingent consideration									(5)	(44)	0
Investment and other income									2	(5)	1
Interest expense									(201)	(39)	(30)
Earnings (loss) before income taxes									(204)	(9)	(32)
Income tax benefit									(76)	(26)	(8)
Net earnings (loss) before equity in subsidiaries									(128)	17	(24)
Income (loss) from equity method investments									686	341	285
Net earnings									558	358	261
(Earnings) loss attributable to noncontrolling interests									1	(2)	7
Net earnings attributable to Centene									$ 559	$ 356	$ 268
Basic earnings per common share (in usd per share)									$ 3.50	$ 2.99	$ 2.30
Diluted earnings per common share (in usd per share)									$ 3.41	$ 2.89	$ 2.23
Basic (in shares)									159,567,607	119,100,744	116,345,764
Diluted (in shares)									163,975,407	123,066,370	120,360,212

Condensed Financial Informat104

Condensed Financial Information Of Registrant (Condensed Statements Of Cash Flows) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash provided by (used in) operating activities	$ 1,851	$ 658	$ 1,223
Purchases of investments	(2,450)	(1,321)	(1,015)
Sales and maturities of investments	1,656	669	406
Investments in acquisitions	(1,297)	(18)	(136)
Other investing activities, net	0	7	0
Net cash used in investing activities	(2,397)	(813)	(848)
Proceeds from borrowings	8,946	1,925	1,875
Payment of long term debt	(6,076)	(1,583)	(1,674)
Common stock repurchases	(63)	(53)	(29)
Debt issue costs	(76)	(4)	(7)
Other financing activities, net	(14)	20	33
Net cash provided by financing activities	2,717	305	198
Net increase in cash and cash equivalents	2,170	150	572
Cash and cash equivalents, beginning of period	1,760	1,610	1,038
Cash and cash equivalents, end of period	3,930	1,760	1,610
Parent Company
Cash provided by (used in) operating activities	(646)	462	317
Capital Contributions To Subsidiaries, net of dividends	(566)	(660)	(384)
Purchases of investments	(112)	(17)	(32)
Sales and maturities of investments	169	9	14
Investments in acquisitions	(2,248)	(113)	(137)
Other investing activities, net	0	7	0
Net cash used in investing activities	(2,757)	(774)	(539)
Proceeds from borrowings	8,934	1,925	1,875
Payment of long term debt	(5,377)	(1,575)	(1,650)
Common stock repurchases	(63)	(53)	(29)
Debt issue costs	(76)	(4)	(7)
Other financing activities, net	(14)	20	33
Net cash provided by financing activities	3,404	313	222
Net increase in cash and cash equivalents	1	1	0
Cash and cash equivalents, beginning of period	4	3	3
Cash and cash equivalents, end of period	$ 5	$ 4	$ 3

Condensed Financial Informat105

Condensed Financial Information Of Registrant Basis of Presentation and Significant Accounting Policies (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2016
Cash flows received by parent from unrestricted subsidiaries	$ 445	$ 341
Senior notes
Senior notes			$ 400

Condensed Financial Informat106

Condensed Financial Information Of Registrant Dividends (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Parent Company
Cash Dividends Paid to Parent Company by Consolidated Subsidiaries	$ 121	$ 11	$ 50