BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of Presentation—In our opinion, all adjustments necessary for a fair presentation of the condensed consolidated financial statements have been included. All such adjustments are of a normal and recurring nature. These condensed consolidated financial statements are unaudited and, accordingly, should be read in conjunction with the consolidated financial statements and notes included in the Annual Report on Form 10-K filed with the SEC on March 4, 2021. Basis of Consolidation—The unaudited condensed consolidated financial statements include the accounts of Root, Inc. and its subsidiaries, all of which are wholly owned. These financial statements have been prepared in accordance with accounting principles generally accepted in the United States, or GAAP. All intercompany accounts and transactions have been eliminated. Use of Estimates—The preparation of the unaudited condensed consolidated financial statements requires management to make certain estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the unaudited condensed consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ from those estimates. Significant estimates reflected in our unaudited condensed consolidated financial statements include, but are not limited to, reserves for loss and loss adjustment expense, premium write-offs and valuation allowances for income taxes. COVID-19—In March 2020, the World Health Organization declared COVID-19 to be a global pandemic. The pandemic and related measures taken to contain the spread of COVID-19, such as government-mandated business closures, orders to “shelter in place” and travel and transportation restrictions, have negatively affected the U.S. and global economies, disrupted global supply chains, and led to unprecedented levels of unemployment. We, and other businesses within the insurance industry, have been impacted by certain individual state bulletins that were issued in 2020 and outlined COVID-19 premium relief efforts, including restrictions on the ability to cancel policies for non-payment, requirements to defer insurance premium payments for up to 60 days and restrictions on increasing policy premiums. The COVID-19 pandemic has impacted and may further impact the broader economic environment, including negatively impacting unemployment levels, economic growth, the proper functioning of financial and capital markets and interest rates. As the COVID-19 pandemic continues to develop, there is uncertainty around the severity and duration of the pandemic and the pandemic’s potential impact on our business and our financial performance. Accordingly, we cannot predict the impact that it may have on our future results of operations and financial condition. Recently Adopted Financial Accounting Standards—In February 2016, the FASB issued Accounting Standards Update No. 2016-02, Leases (Topic 842). The main provision of ASU 2016-02 requires the recognition of right-of-use lease assets and lease liabilities by lessees for those leases classified as operating leases under previous GAAP. The guidance also requires disclosures that meet the objective of enabling financial statement users to assess the amount, timing, and uncertainty of related cash flows. We adopted ASU 2016-02 on January 1, 2021. We elected various practical expedients which include not applying the amended lease accounting guidance to comparative periods; including the carry forward of our leases without reassessing whether any contracts are leases or contain leases, lease classification and initial direct costs; and excluding leases with a term of 12 months or less from lease liability and right-of-use asset recognition. We did not elect the hindsight practical expedient. Our lease agreements contain lease components and non-lease components, both of which we have elected to account for as a single lease component for our real estate asset class. Operating lease expense for operating lease right of use assets is recognized on a straight-line basis over the lease term, which may include options to extend or terminate the lease when it is reasonably certain to do so and there is a significant economic incentive to exercise that option. Upon adoption of ASU 2016-02, we recognized an operating lease liability of $16.2 million and corresponding right of use asset of $9.9 million, which includes the effect of $6.3 million from reclassifying previously recognized deferred rent and lease exit liabilities as an offset, in accordance with the transition guidance. These lease assets and liabilities are recorded as other assets and other liabilities on the condensed consolidated balance sheets. This transition adjustment was reflected as a non-cash transaction in our condensed consolidated statements of cash flows. The transition did not have a material impact on our results of operations, liquidity or debt covenant compliance under our current debt agreements. For additional information refer to Note 6, “Leases.” Upcoming Accounting Pronouncements—We currently qualify as an "emerging growth company" under the Jumpstart Our Business Startups Act of 2012, whereby we have the option to adopt new or revised accounting guidance within the same time periods as private companies. We have elected this option, but may ultimately determine it is preferable to take advantage of early adoption provisions offered within the applicable guidance. In June 2016, the FASB issued ASU 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. ASU 2016-13 amends previous guidance on the impairment of financial instruments by adding an impairment model that allows an entity to recognize expected credit losses as an allowance rather than impairing as they are incurred. The new guidance is intended to reduce complexity of credit impairment models and result in a more timely recognition of expected credit losses. The effective date of ASU 2016-13 is for reporting periods beginning after December 15, 2022. We are currently evaluating the impact of ASU 2016-13.