Summary of Significant Accounting Policies (Policies)	9 Months Ended
Sep. 30, 2021
Basis of presentation	Basis of Presentation The consolidated financial statements included herein have been prepared by Repligen Corporation (the “Company”, “Repligen”, “our” or “we”) in accordance with generally accepted accounting principles in the United States (“GAAP”) and pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”), for Quarterly Reports on Form 10-Q and Article 10 of Regulation S-X and do not include all of the information and footnote disclosures required by GAAP. These consolidated financial statements should be read in conjunction with the audited consolidated financial statements and accompanying notes thereto included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020, which was filed with the SEC on February 24, 2021 (“Form 10-K”). The preparation of 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. The business and economic uncertainty resulting from the novel coronavirus (“COVID-19”) pandemic has made such estimates more difficult to calculate. Accordingly, actual results could differ from those estimates. The consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries, Repligen Sweden AB, Repligen GmbH, Spectrum® LifeSciences LLC and its subsidiaries (“Spectrum”), C Technologies, Inc. (“C Technologies”), Non-Metallic Solutions, Inc. (“NMS”), ARTeSYN Biosolutions Holdings Ireland Limited (“ARTeSYN”), Polymem S.A. (“Polymem”), Avitide, Inc. (“Avitide”) and Repligen Singapore Pte. Ltd. All significant intercompany accounts and transactions have been eliminated in consolidation. The Company made no material changes in the application of its significant accounting policies that were disclosed in its Form 10-K. In the opinion of management, the accompanying unaudited consolidated financial statements include all adjustments, consisting of only normal, recurring adjustments necessary for a fair presentation of the financial position, results of operations and cash flows. The results of operations for the interim periods presented are not necessarily indicative of results to be expected for the entire year. Certain prior year balances have been reclassified to conform to current year presentation.
Recent Accounting Standards Updates	Recent Accounting Standards Updates We consider the applicability and impact of all Accounting Standards Updates (“ASUs” or “ASU”) on the Company’s consolidated financial statements. Updates not listed below were assessed and determined to be either not applicable or are expected to have minimal impact on the Company’s consolidated financial position or results of operations. Recently issued ASUs that we feel may be applicable to the Company are as follows: Recently Issued Accounting Standard Updates – Not Yet Adopted In August 2020, the Financial Accounting Standards Board (“FASB”) issued ASU 2020-06, “Debt - Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging - Contracts in Entity’s Own Equity (Subtopic 815-40).” ASU 2020-06 simplifies the accounting for convertible debt instruments and convertible preferred stock by reducing the number of accounting models and the number of embedded conversion features that could be recognized separately from the primary contract. ASU 2020-06 also enhances transparency and improves disclosures for convertible instruments and earnings per share guidance. ASU 2020-06 is effective for annual reporting periods beginning after December 15, 2021, including interim periods within those fiscal years. Early adoption is permitted, but no earlier than fiscal years beginning after December 15, 2020. This update permits the use of either the modified retrospective or fully retrospective method of transition. The Company is currently evaluating the impact of the adoption of ASU 2020-06 on the Company's consolidated financial statements.

Summary of Significant Accounting Policies (Policies)

9 Months Ended

Sep. 30, 2021

Basis of Presentation

The consolidated financial statements included herein have been prepared by Repligen Corporation (the “Company”, “Repligen”, “our” or “we”) in accordance with generally accepted accounting principles in the United States (“GAAP”) and pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”), for Quarterly Reports on Form 10-Q and Article 10 of Regulation S-X and do not include all of the information and footnote disclosures required by GAAP. These consolidated financial statements should be read in conjunction with the audited consolidated financial statements and accompanying notes thereto included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020, which was filed with the SEC on February 24, 2021 (“Form 10-K”).

The preparation of 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. The business and economic uncertainty resulting from the novel coronavirus (“COVID-19”) pandemic has made such estimates more difficult to calculate. Accordingly, actual results could differ from those estimates.

The consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries, Repligen Sweden AB, Repligen GmbH, Spectrum® LifeSciences LLC and its subsidiaries (“Spectrum”), C Technologies, Inc. (“C Technologies”), Non-Metallic Solutions, Inc. (“NMS”), ARTeSYN Biosolutions Holdings Ireland Limited (“ARTeSYN”), Polymem S.A. (“Polymem”), Avitide, Inc. (“Avitide”) and Repligen Singapore Pte. Ltd. All significant intercompany accounts and transactions have been eliminated in consolidation.

The Company made no material changes in the application of its significant accounting policies that were disclosed in its Form 10-K. In the opinion of management, the accompanying unaudited consolidated financial statements include all adjustments, consisting of only normal, recurring adjustments necessary for a fair presentation of the financial position, results of operations and cash flows. The results of operations for the interim periods presented are not necessarily indicative of results to be expected for the entire year. Certain prior year balances have been reclassified to conform to current year presentation.

Recent Accounting Standards Updates

We consider the applicability and impact of all Accounting Standards Updates (“ASUs” or “ASU”) on the Company’s consolidated financial statements. Updates not listed below were assessed and determined to be either not applicable or are expected to have minimal impact on the Company’s consolidated financial position or results of operations. Recently issued ASUs that we feel may be applicable to the Company are as follows:

Recently Issued Accounting Standard Updates – Not Yet Adopted

In August 2020, the Financial Accounting Standards Board (“FASB”) issued ASU 2020-06, “Debt - Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging - Contracts in Entity’s Own Equity (Subtopic 815-40).” ASU 2020-06 simplifies the accounting for convertible debt instruments and convertible preferred stock by reducing the number of accounting models and the number of embedded conversion features that could be recognized separately from the primary contract. ASU 2020-06 also enhances transparency and improves disclosures for convertible instruments and earnings per share guidance. ASU 2020-06 is effective for annual reporting periods beginning after December 15, 2021, including interim periods within those fiscal years. Early adoption is permitted, but no earlier than fiscal years beginning after December 15, 2020. This update permits the use of either the modified retrospective or fully retrospective method of transition. The Company is currently evaluating the impact of the adoption of ASU 2020-06 on the Company's consolidated financial statements.