Basis of Presentation (Notes)	9 Months Ended
Sep. 30, 2021
Basis of Presentation and Significant Accounting Policies [Text Block]	Basis of Presentation UnitedHealth Group Incorporated (individually and together with its subsidiaries, “UnitedHealth Group” and “the Company”) is a diversified health care company with a mission to help people live healthier lives and help make the health system work better for everyone. Our two complementary business platforms — Optum and UnitedHealthcare — are driven by this unified mission and vision to improve health care access, affordability, experiences and outcomes for the individuals and organizations we are privileged to serve. The Company has prepared the Condensed Consolidated Financial Statements according to U.S. Generally Accepted Accounting Principles (GAAP) and has included the accounts of UnitedHealth Group and its subsidiaries. The year-end condensed consolidated balance sheet was derived from audited financial statements, but does not include all disclosures required by GAAP. In accordance with the rules and regulations of the U.S. Securities and Exchange Commission (SEC), the Company has omitted certain footnote disclosures that would substantially duplicate the disclosures contained in its annual audited Consolidated Financial Statements. Therefore, these Condensed Consolidated Financial Statements should be read together with the Consolidated Financial Statements and the Notes included in Part II, Item 8, “Financial Statements” in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020 as filed with the SEC (2020 10-K). The accompanying Condensed Consolidated Financial Statements include all normal recurring adjustments necessary to present the interim financial statements fairly. Use of Estimates These Condensed Consolidated Financial Statements include certain amounts based on the Company’s best estimates and judgments. The Company’s most significant estimates relate to estimates and judgments for medical costs payable and goodwill. Certain of these estimates require the application of complex assumptions and judgments, often because they involve matters that are inherently uncertain and will likely change in subsequent periods. The impact of any change in estimates is included in earnings in the period in which the estimate is adjusted.

Basis of Presentation (Notes)

9 Months Ended

Sep. 30, 2021

Basis of Presentation and Significant Accounting Policies [Text Block]

Basis of Presentation

UnitedHealth Group Incorporated (individually and together with its subsidiaries, “UnitedHealth Group” and “the Company”) is a diversified health care company with a mission to help people live healthier lives and help make the health system work better for everyone. Our two complementary business platforms — Optum and UnitedHealthcare — are driven by this unified mission and vision to improve health care access, affordability, experiences and outcomes for the individuals and organizations we are privileged to serve.

The Company has prepared the Condensed Consolidated Financial Statements according to U.S. Generally Accepted Accounting Principles (GAAP) and has included the accounts of UnitedHealth Group and its subsidiaries. The year-end condensed consolidated balance sheet was derived from audited financial statements, but does not include all disclosures required by GAAP. In accordance with the rules and regulations of the U.S. Securities and Exchange Commission (SEC), the Company has omitted certain footnote disclosures that would substantially duplicate the disclosures contained in its annual audited Consolidated Financial Statements. Therefore, these Condensed Consolidated Financial Statements should be read together with the Consolidated Financial Statements and the Notes included in Part II, Item 8, “Financial Statements” in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020 as filed with the SEC (2020 10-K). The accompanying Condensed Consolidated Financial Statements include all normal recurring adjustments necessary to present the interim financial statements fairly.

Use of Estimates

These Condensed Consolidated Financial Statements include certain amounts based on the Company’s best estimates and judgments. The Company’s most significant estimates relate to estimates and judgments for medical costs payable and goodwill. Certain of these estimates require the application of complex assumptions and judgments, often because they involve matters that are inherently uncertain and will likely change in subsequent periods. The impact of any change in estimates is included in earnings in the period in which the estimate is adjusted.