Basis of Presentation and Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2016
Accounting Policies [Abstract]
Basis of presentation	Basis of Presentation In our opinion, the accompanying unaudited interim consolidated financial statements include all adjustments, consisting of normal recurring adjustments, which are necessary to fairly state our financial position, results of operations, and cash flows. The consolidated balance sheet at December 31, 2015, has been derived from audited financial statements as of that date. The interim consolidated results of operations are not necessarily indicative of the results that may occur for the full fiscal year. Certain footnote disclosure normally included in financial statements prepared in accordance with United States of America generally accepted accounting principles (“GAAP”) has been omitted pursuant to instructions, rules, and regulations prescribed by the United States Securities and Exchange Commission (“SEC”). The disclosures provided herein should be read in conjunction with the audited financial statements and notes thereto included in our 2015 Form 10-K.
Consolidation	As discussed in Note 4, amounts for the nine months ended September 30, 2015, presented in our unaudited consolidated financial statements and notes to unaudited consolidated financial statements for that period, include the historical operations of our predecessor entity, Evolent Health Holdings, which did not consolidate the operations of Evolent Health LLC for the entire nine month period. The amounts as of and for the three and nine months ended September 30, 2016, reflect our operations, which consolidate the operations of Evolent Health LLC. All inter-company accounts and transactions have been eliminated in consolidation.
Restricted cash	Restricted Cash Restricted cash is carried at cost, which approximates fair value, and includes cash used to collateralize various contractual obligations
Adoption of new accounting standards and future adoption of new accounting standards	Adoption of New Accounting Standards In March 2016, the FASB issued ASU 2016-09, Compensation – Stock Compensation: Improvements to Employee Share-Based Payment Accounting. The update simplifies several aspects of the accounting for employee share-based payment transactions, including accounting for income taxes, forfeitures and statutory tax withholding requirements, as well as classification in the statement of cash flows. This standard is effective for annual periods beginning after December 15, 2016, and interim periods within those annual periods, with early adoption permitted for any interim or annual period. The Company elected to early adopt this ASU during the second quarter of 2016, as described in Note 2 above. Future Adoption of New Accounting Standards In August 2016, the FASB issued ASU 2016-15, Statement of Cash Flows - Classification of Certain Cash Receipts and Cash Payments. This ASU provides updated guidance on eight specific cash flow issues to reduce diversity in practice in how certain cash receipts and cash payments are presented and classified in the statement of cash flows. The amendments are effective for public business entities for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years. Early adoption is permitted, including adoption in an interim period. If an entity early adopts the amendments in an interim period, any adjustments should be reflected as of the beginning of the fiscal year that includes that interim period. We intend to adopt the requirements of this standard effective January 1, 2018 and are currently evaluating the impact of the adoption on our statement of cash flows. In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses: Measurement of Credit Losses on Financial Instruments. With respect to assets measured at amortized cost, such as held-to-maturity assets, the update requires presentation of the amortized cost net of a credit loss allowance. The update eliminates the probable initial recognition threshold that was previously required prior to recognizing a credit loss on financial instruments. The credit loss estimate can now reflect an entity’s current estimate of all future expected credit losses as opposed to the previous standard, when an entity only considered past events and current conditions. With respect to available for sale debt securities, the update requires that credit losses be presented as an allowance rather than as a write-down. The update is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. Early adoption is permitted as of the fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. We intend to adopt the requirements of this standard effective January 1, 2020 and are currently evaluating the impact of the adoption on our financial condition and results of operations. In February 2016, the FASB issued ASU 2016-02, Leases, in order to establish the principles to report transparent and economically neutral information about the assets and liabilities that arise from leases. This update introduces a new standard on accounting for leases, including a lessee model that brings most leases on the balance sheet. The new standard also aligns many of the underlying principles of the new lessor model with those in ASC 606, the FASB’s new revenue recognition standard (e.g., those related to evaluating when profit can be recognized). 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. The ASU is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Early application is permitted. We intend to adopt the requirements of this standard effective January 1, 2019, and are currently evaluating the impact of the adoption on our financial condition and results of operations. In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers, in order to clarify the principles of recognizing revenue. This standard establishes the core principle of recognizing revenue to depict the transfer of promised goods or services in an amount that reflects the consideration the entity expects to be entitled in exchange for those goods or services. The FASB defines a five-step process that systematically identifies the various components of the revenue recognition process, culminating with the recognition of revenue upon satisfaction of an entity’s performance obligation. By completing all five steps of the process, the core principles of revenue recognition will be achieved. In March 2016, the FASB issued an update to the new revenue standard (ASU 2014-09) in the form of ASU 2016-08, which amended the principal-versus-agent implementation guidance and illustrations in the new revenue guidance. The update clarifies that an entity should evaluate whether it is the principal or the agent for each specified good or service promised in a contract with a customer. In April 2016, the FASB issued another update to the new revenue standard in the form of ASU 2016-10, which amended the guidance on identifying performance obligations and the implementation guidance on licensing. These ASUs were followed by two further updates issued during May 2016, including ASU 2016-11, which rescinds certain SEC guidance, such as the adoption of ASUs 2014-09 and 2014-16, including accounting for consideration given by a vendor to a customer, and ASU 2016-12, which is intended to clarify the objective of the collectability criterion while identifying the contract(s) with a customer. The new revenue standard (including updates) will be effective for annual and interim reporting periods beginning after December 15, 2017, with early adoption permitted only as of annual reporting periods beginning after December 15, 2016. We intend to adopt the requirements of this standard effective January 1, 2018, and, while we are evaluating the impact to our financial condition and results of operations, we expect the adoption of this ASU to require the inclusion of additional disclosures surrounding the nature and timing of our revenue. In August 2014, the FASB issued ASU 2014-15, Presentation of Financial Statements – Going Concern: Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern. This standard requires management to assess an entity’s ability to continue as a going concern by incorporating and expanding upon certain principles that are currently in U.S. auditing standards by requiring an assessment for a period of one year after the date that the financial statements are issued. Further, based on certain conditions and circumstances, additional disclosures may be required. This standard is effective beginning with the first annual period ending after December 15, 2016, and for all annual and interim periods thereafter. Early application is permitted.
Fair value measurement	Nonrecurring Fair Value Measurements In addition to the assets and liabilities that are recorded at fair value on a recurring basis, the Company records certain assets and liabilities at fair value on a nonrecurring basis as required by GAAP. Generally, assets are recorded at fair value on a nonrecurring basis as a result of impairment charges. This includes goodwill, intangible assets, property, plant and equipment, held-to-maturity investments and equity method investments. While not carried at fair value on a recurring basis, these items are continually monitored for indicators of impairment that would indicate current carrying value is greater than fair value. In those situations, the assets are considered impaired and written down to current fair value. Refer to Notes 6, 7 and 12 for further discussion of assets measured at fair value on a nonrecurring basis. Other Fair Value Disclosures The carrying amounts of cash and cash equivalents (those not held in a money market fund), restricted cash, receivables, prepaid expenses, accrued liabilities, accrued compensation and deferred rent approximate their fair values because of the relatively short-term maturities of these items and financial instruments.