SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	6 Months Ended
Jun. 30, 2022
Accounting Policies [Abstract]
Basis of Presentation and Principles of Consolidation	Basis of Presentation and Principles of ConsolidationThe accompanying condensed consolidated financial statements, which include the accounts of Exact Sciences Corporation and those of its wholly owned subsidiaries and variable interest entities, are unaudited and have been prepared on a basis substantially consistent with the Company’s audited financial statements and notes as of and for the year ended December 31, 2021 included in the Company’s Annual Report on Form 10-K (the “2021 Form 10-K”). All intercompany transactions and balances have been eliminated upon consolidation. These condensed consolidated financial statements are prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”) and follow the requirements of the Securities and Exchange Commission (“SEC”) for interim reporting. In the opinion of management, the accompanying unaudited condensed consolidated financial statements contain all adjustments (consisting only of adjustments of a normal and recurring nature) considered necessary for a fair statement of its financial position, operating results and cash flows for the periods presented. The condensed consolidated balance sheet at December 31, 2021 has been derived from audited financial statements, but does not contain all of the footnote disclosures from the 2021 Form 10-K. The results of the Company’s operations for any interim period are not necessarily indicative of the results of the Company’s operations for any other interim period or for a full fiscal year. The statements should be read in conjunction with the audited financial statements and related notes included in the 2021 Form 10-K.
Use of Estimates	Use of Estimates The preparation of the condensed consolidated financial statements in conformity with 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. Critical accounting policies are those that affect the Company’s financial statements materially and involve difficult, subjective or complex judgments by management, and actual results could differ from those estimates. These estimates include revenue recognition, valuation of intangible assets and goodwill, and accounting for income taxes among others. The Company’s critical accounting policies and estimates are explained further in the notes to the condensed consolidated financial statements in this Quarterly Report and the 2021 Form 10-K. The spread of the coronavirus (“COVID-19”) has affected many segments of the global economy, including the cancer screening and diagnostics industry. The Company assessed certain accounting matters that generally require consideration of forecasted financial information in context with the information reasonably available to the Company and the unknown future impacts of COVID-19 as of June 30, 2022 and through the date of the filing of this Quarterly Report on Form 10-Q. The accounting matters assessed included, but were not limited to, the Company’s allowance for doubtful accounts and credit losses, marketable and non-marketable investments, software, and the carrying value of the goodwill and other long-lived assets. The Company’s future assessment of the magnitude and duration of COVID-19, as well as other factors, could result in additional material impacts to the Company’s consolidated financial statements in future reporting periods. The pandemic and related precautionary measures began to materially disrupt the Company's operations in March 2020 and may continue to disrupt the business for an unknown period of time. As a result, the pandemic had an impact on the Company’s revenues and operating results. The ultimate impact of COVID-19 depends on factors beyond the Company’s knowledge or control, including the duration and severity of the outbreak, as well as third-party actions taken to contain its spread and mitigate its public health effects. As a result, the Company is unable to estimate the extent to which COVID-19 will negatively impact its financial results or liquidity.
Collateralized Debt Instruments	Collateralized Debt InstrumentsDebt instruments that are collateralized by security interests in financial assets held by the Company are accounted for as a secured borrowing and therefore: (i) the asset balances pledged as collateral are included within the applicable balance sheet line item and the borrowings are included within long-term debt in the condensed consolidated balance sheet; (ii) interest expense is included within the condensed consolidated statements of operations; and (iii) in the case of collateralized accounts receivable, receipts from customers related to the underlying accounts receivable are reflected as operating cash flows, and (iv) borrowings and repayments under the collateralized loans are reflected as financing cash flows within the condensed consolidated statements of cash flows.
Reclassifications	Reclassifications Certain prior year amounts have been reclassified to conform to the current year presentation in the condensed consolidated financial statements and accompanying notes to the condensed consolidated financial statements.
Recent Accounting Pronouncements	Recent Accounting Pronouncements Recently Adopted Accounting Pronouncements In October 2021, The Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2021-08, Business Combinations (Topic 805). This update requires that an entity (acquirer) recognize and measure contract assets and contract liabilities acquired in a business combination in accordance with Accounting Standards Codification (“ASC”) 606. This differs from the current requirement to measure contract assets and contract liabilities acquired in a business combination at fair value. The amendments in this update should be applied prospectively, and are effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. Early adoption is permitted, including adoption in an interim period. The Company early adopted the amendments in this update during the first quarter of fiscal year 2022. There was no material impact to the Company’s condensed consolidated financial statements.
Net Loss Per Share	Net Loss Per Share Basic net loss per common share was determined by dividing net loss applicable to common stockholders by the weighted average common shares outstanding during the period. Basic and diluted net loss per share is the same because all outstanding common stock equivalents have been excluded, as they are anti-dilutive as a result of the Company’s losses.

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)

6 Months Ended

Jun. 30, 2022

Basis of Presentation and Principles of Consolidation

Basis of Presentation and Principles of ConsolidationThe accompanying condensed consolidated financial statements, which include the accounts of Exact Sciences Corporation and those of its wholly owned subsidiaries and variable interest entities, are unaudited and have been prepared on a basis substantially consistent with the Company’s audited financial statements and notes as of and for the year ended December 31, 2021 included in the Company’s Annual Report on Form 10-K (the “2021 Form 10-K”). All intercompany transactions and balances have been eliminated upon consolidation. These condensed consolidated financial statements are prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”) and follow the requirements of the Securities and Exchange Commission (“SEC”) for interim reporting. In the opinion of management, the accompanying unaudited condensed consolidated financial statements contain all adjustments (consisting only of adjustments of a normal and recurring nature) considered necessary for a fair statement of its financial position, operating results and cash flows for the periods presented. The condensed consolidated balance sheet at December 31, 2021 has been derived from audited financial statements, but does not contain all of the footnote disclosures from the 2021 Form 10-K. The results of the Company’s operations for any interim period are not necessarily indicative of the results of the Company’s operations for any other interim period or for a full fiscal year. The statements should be read in conjunction with the audited financial statements and related notes included in the 2021 Form 10-K.

Use of Estimates

The preparation of the condensed consolidated financial statements in conformity with 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. Critical accounting policies are those that affect the Company’s financial statements materially and involve difficult, subjective or complex judgments by management, and actual results could differ from those estimates. These estimates include revenue recognition, valuation of intangible assets and goodwill, and accounting for income taxes among others. The Company’s critical accounting policies and estimates are explained further in the notes to the condensed consolidated financial statements in this Quarterly Report and the 2021 Form 10-K.

The spread of the coronavirus (“COVID-19”) has affected many segments of the global economy, including the cancer screening and diagnostics industry. The Company assessed certain accounting matters that generally require consideration of forecasted financial information in context with the information reasonably available to the Company and the unknown future impacts of COVID-19 as of June 30, 2022 and through the date of the filing of this Quarterly Report on Form 10-Q. The accounting matters assessed included, but were not limited to, the Company’s allowance for doubtful accounts and credit losses, marketable and non-marketable investments, software, and the carrying value of the goodwill and other long-lived assets. The Company’s future assessment of the magnitude and duration of COVID-19, as well as other factors, could result in additional material impacts to the Company’s consolidated financial statements in future reporting periods.

The pandemic and related precautionary measures began to materially disrupt the Company's operations in March 2020 and may continue to disrupt the business for an unknown period of time. As a result, the pandemic had an impact on the Company’s revenues and operating results.

The ultimate impact of COVID-19 depends on factors beyond the Company’s knowledge or control, including the duration and severity of the outbreak, as well as third-party actions taken to contain its spread and mitigate its public health effects. As a result, the Company is unable to estimate the extent to which COVID-19 will negatively impact its financial results or liquidity.

Collateralized Debt Instruments

Collateralized Debt InstrumentsDebt instruments that are collateralized by security interests in financial assets held by the Company are accounted for as a secured borrowing and therefore: (i) the asset balances pledged as collateral are included within the applicable balance sheet line item and the borrowings are included within long-term debt in the condensed consolidated balance sheet; (ii) interest expense is included within the condensed consolidated statements of operations; and (iii) in the case of collateralized accounts receivable, receipts from customers related to the underlying accounts receivable are reflected as operating cash flows, and (iv) borrowings and repayments under the collateralized loans are reflected as financing cash flows within the condensed consolidated statements of cash flows.

Reclassifications

Certain prior year amounts have been reclassified to conform to the current year presentation in the condensed consolidated financial statements and accompanying notes to the condensed consolidated financial statements.

Recent Accounting Pronouncements

Recently Adopted Accounting Pronouncements

In October 2021, The Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2021-08, Business Combinations (Topic 805). This update requires that an entity (acquirer) recognize and measure contract assets and contract liabilities acquired in a business combination in accordance with Accounting Standards Codification (“ASC”) 606. This differs from the current requirement to measure contract assets and contract liabilities acquired in a business combination at fair value. The amendments in this update should be applied prospectively, and are effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. Early adoption is permitted, including adoption in an interim period. The Company early adopted the amendments in this update during the first quarter of fiscal year 2022. There was no material impact to the Company’s condensed consolidated financial statements.

Net Loss Per Share

Basic net loss per common share was determined by dividing net loss applicable to common stockholders by the weighted average common shares outstanding during the period. Basic and diluted net loss per share is the same because all outstanding common stock equivalents have been excluded, as they are anti-dilutive as a result of the Company’s losses.