Significant Accounting Policies (Policies)	3 Months Ended
Mar. 31, 2022
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The interim consolidated financial statements are unaudited but, in the opinion of management, reflect all adjustments necessary for a fair statement of the Company’s consolidated financial position, results of operations and cash flows for the periods presented. These adjustments consist of normal, recurring items. The results of operations for any interim period are not necessarily indicative of results for the full year. The interim consolidated financial statements and notes are presented as permitted by the requirements for Quarterly Reports on Form 10-Q. This Quarterly Report on Form 10-Q should be read in conjunction with the Company’s consolidated financial statements and notes included in its most recent Annual Report on Form 10-K. Effective in the first quarter of 2022, 3M made changes in the measure of segment operating performance used by 3M’s chief operating decision maker—impacting 3M’s disclosed measure of segment profit/loss (business segment operating income). See additional information in Note 16. 3M's disclosed disaggregated revenue was also updated as a result of the changes in segment reporting. See additional information in Note 2. Information provided herein reflects the impact of these changes for all periods presented.
Consolidation and foreign currency translation	Consolidation and foreign currency translation Local currencies generally are considered the functional currencies outside the United States with the exception of 3M’s subsidiaries in Argentina, the economy of which is considered highly inflationary and, accordingly, the financial statements of these subsidiaries are remeasured as if their functional currency is that of their parent. Assets and liabilities for operations in local-currency environments are translated at month-end exchange rates of the period reported. Income and expense items are translated at average monthly currency exchange rates in effect during the period. Cumulative translation adjustments are recorded as a component of accumulated other comprehensive income (loss) in shareholders’ equity. 3M has subsidiaries in Turkey. Based on underlying indices, Turkey’s cumulative three-year inflation rate exceeded 100 percent in the first quarter of 2022, thus being considered highly inflationary. As a result, the financial statements of the Turkish subsidiaries will be remeasured as if their functional currency were that of their parent, starting in the second quarter of 2022. The operating income and balances of underlying net monetary assets denominated in Turkish lira are not material to 3M.
Earnings Per Share	Earnings Per ShareThe difference in the weighted average 3M shares outstanding for calculating basic and diluted earnings per share attributable to 3M common shareholders is a result of the dilution associated with the Company’s stock-based compensation plans. Certain options outstanding under these stock-based compensation plans were not included in the computation of diluted earnings per share attributable to 3M common shareholders because they would have had an anti-dilutive effect of 23.1 million average options for the three months ended March 31, 2022 and 8.7 million average options for the three months ended March 31, 2021.
New Accounting Pronouncements	New Accounting Pronouncements Refer to Note 1 to the Consolidated Financial Statements in 3M’s 2021 Annual Report on Form 10-K for a discussion of applicable standards issued and not yet adopted by 3M.
Business Segments	3M’s businesses are organized, managed and internally grouped into segments based on differences in markets, products, technologies and services. 3M manages its operations in four business segments: Safety and Industrial; Transportation and Electronics; Health Care; and Consumer. 3M’s four business segments bring together common or related 3M technologies, enhancing the development of innovative products and services and providing for efficient sharing of business resources. Transactions among reportable segments are recorded at cost. 3M is an integrated enterprise characterized by substantial intersegment cooperation, cost allocations and inventory transfers. Therefore, management does not represent that these segments, if operated independently, would report the operating income information shown. 3M discloses business segment operating income as its measure of segment profit/loss, reconciled to both total 3M operating income and income before taxes. Business segment operating income excludes certain expenses and income that are not allocated to business segments (as described below in “Corporate and Unallocated”). Effective in the first quarter of 2022, the measure of segment operating performance used by 3M’s chief operating decision maker (CODM) changed and, as a result, 3M’s disclosed measure of segment profit/loss (business segment operating income) was updated. The change to business segment operating income aligns with the update to how the CODM assesses performance and allocates resources for the Company’s business segments. The changes included the items described below. The financial information presented herein reflects the impact of these business segment reporting changes for all periods presented. Eliminating inclusion of dual credit in measure of segment operating performance 3M business segment operating performance measures were updated to no longer include dual credit to business segments for certain sales and related operating income. Management previously evaluated its business segments based on net sales and operating income performance, including dual credit reporting. 3M reflected additional (“dual”) credit to another business segment when the customer account activity (“sales district”) with respect to the particular product sold to the external customer was provided by a different business segment. For example, privacy screen protection products are primarily sold by the Display Materials and Systems Division within the Transportation and Electronics business segment; however, certain sales districts within the Consumer business segment provide the customer account activity for sales of the product to particular customers. In this example, the non-primary selling segment (Consumer) previously would also have received credit for the associated net sales initiated through its sales district and the related approximate operating income. The offset to the dual credit business segment reporting was reflected as a reconciling item entitled “Elimination of Dual Credit,” such that sales and operating income in total were unchanged. Reflecting certain litigation-related costs in the Safety and Industrial segment's operating performance measure 3M's business segment operating performance measure with respect to its Safety and Industrial business segment was updated relative to litigation-related costs for respirator mask/asbestos litigation matters. Previously, 3M included these costs, when significant, as a special item (as further described below) within Corporate and Unallocated. 3M now includes all litigation-related costs associated with respirator mask/asbestos litigation matters within the Safety and Industrial business segment (along with other Safety and Industrial matters already included therein, such as those related to Combat Arms Earplugs). Corporate and Unallocated Corporate and Unallocated operating income includes “corporate special items” and “other corporate expense-net”. Corporate special items include net costs for significant litigation associated with PFAS-related other environmental matters (see Note 14), gain/loss on sale of businesses (see Note 3), and divestiture-related restructuring costs. Other corporate expense-net includes items such as net costs related to limited unallocated corporate staff and centrally managed material resource centers of expertise costs, corporate philanthropic activity, and other net costs that 3M may choose not to allocate directly to its business segments. Other corporate expense-net also includes costs and income from contract manufacturing, transition services and other arrangements with the acquirer of the former Drug Delivery business following its 2020 divestiture. Items classified as revenue from this activity are included in Corporate and Unallocated net sales. Because Corporate and Unallocated includes a variety of miscellaneous items, it is subject to fluctuation on a quarterly and annual basis.

Significant Accounting Policies (Policies)

3 Months Ended

Mar. 31, 2022

The interim consolidated financial statements are unaudited but, in the opinion of management, reflect all adjustments necessary for a fair statement of the Company’s consolidated financial position, results of operations and cash flows for the periods presented. These adjustments consist of normal, recurring items. The results of operations for any interim period are not necessarily indicative of results for the full year. The interim consolidated financial statements and notes are presented as permitted by the requirements for Quarterly Reports on Form 10-Q. This Quarterly Report on Form 10-Q should be read in conjunction with the Company’s consolidated financial statements and notes included in its most recent Annual Report on Form 10-K.

Effective in the first quarter of 2022, 3M made changes in the measure of segment operating performance used by 3M’s chief operating decision maker—impacting 3M’s disclosed measure of segment profit/loss (business segment operating income). See additional information in Note 16. 3M's disclosed disaggregated revenue was also updated as a result of the changes in segment reporting. See additional information in Note 2. Information provided herein reflects the impact of these changes for all periods presented.

Consolidation and foreign currency translation

Local currencies generally are considered the functional currencies outside the United States with the exception of 3M’s subsidiaries in Argentina, the economy of which is considered highly inflationary and, accordingly, the financial statements of these subsidiaries are remeasured as if their functional currency is that of their parent. Assets and liabilities for operations in local-currency environments are translated at month-end exchange rates of the period reported. Income and expense items are translated at average monthly currency exchange rates in effect during the period. Cumulative translation adjustments are recorded as a component of accumulated other comprehensive income (loss) in shareholders’ equity.

3M has subsidiaries in Turkey. Based on underlying indices, Turkey’s cumulative three-year inflation rate exceeded 100 percent in the first quarter of 2022, thus being considered highly inflationary. As a result, the financial statements of the Turkish subsidiaries will be remeasured as if their functional currency were that of their parent, starting in the second quarter of 2022. The operating income and balances of underlying net monetary assets denominated in Turkish lira are not material to 3M.

Earnings Per Share

Earnings Per ShareThe difference in the weighted average 3M shares outstanding for calculating basic and diluted earnings per share attributable to 3M common shareholders is a result of the dilution associated with the Company’s stock-based compensation plans. Certain options outstanding under these stock-based compensation plans were not included in the computation of diluted earnings per share attributable to 3M common shareholders because they would have had an anti-dilutive effect of 23.1 million average options for the three months ended March 31, 2022 and 8.7 million average options for the three months ended March 31, 2021.

New Accounting Pronouncements

Refer to Note 1 to the Consolidated Financial Statements in 3M’s 2021 Annual Report on Form 10-K for a discussion of applicable standards issued and not yet adopted by 3M.

Business Segments

3M’s businesses are organized, managed and internally grouped into segments based on differences in markets, products, technologies and services. 3M manages its operations in four business segments: Safety and Industrial; Transportation and Electronics; Health Care; and Consumer. 3M’s four business segments bring together common or related 3M technologies, enhancing the development of innovative products and services and providing for efficient sharing of business resources. Transactions among reportable segments are recorded at cost. 3M is an integrated enterprise characterized by substantial intersegment cooperation, cost allocations and inventory transfers. Therefore, management does not represent that these segments, if operated independently, would report the operating income information shown.

3M discloses business segment operating income as its measure of segment profit/loss, reconciled to both total 3M operating income and income before taxes. Business segment operating income excludes certain expenses and income that are not allocated to business segments (as described below in “Corporate and Unallocated”).

Effective in the first quarter of 2022, the measure of segment operating performance used by 3M’s chief operating decision maker (CODM) changed and, as a result, 3M’s disclosed measure of segment profit/loss (business segment operating income) was updated. The change to business segment operating income aligns with the update to how the CODM assesses performance and allocates resources for the Company’s business segments. The changes included the items described below. The financial information presented herein reflects the impact of these business segment reporting changes for all periods presented.

Eliminating inclusion of dual credit in measure of segment operating performance

3M business segment operating performance measures were updated to no longer include dual credit to business segments for certain sales and related operating income. Management previously evaluated its business segments based on net sales and operating income performance, including dual credit reporting. 3M reflected additional (“dual”) credit to another business segment when the customer account activity (“sales district”) with respect to the particular product sold to the external customer was provided by a different business segment. For example, privacy screen protection products are primarily sold by the Display Materials and Systems Division within the Transportation and Electronics business segment; however, certain sales districts within the Consumer business segment provide the customer account activity for sales of the product to particular customers. In this example, the non-primary selling segment (Consumer) previously would also have received credit for the associated net sales initiated through its sales district and the related approximate operating income. The offset to the dual credit business segment reporting was reflected as a reconciling item entitled “Elimination of Dual Credit,” such that sales and operating income in total were unchanged.

Reflecting certain litigation-related costs in the Safety and Industrial segment's operating performance measure

3M's business segment operating performance measure with respect to its Safety and Industrial business segment was updated relative to litigation-related costs for respirator mask/asbestos litigation matters. Previously, 3M included these costs, when significant, as a special item (as further described below) within Corporate and Unallocated. 3M now includes all litigation-related costs associated with respirator mask/asbestos litigation matters within the Safety and Industrial business segment (along with other Safety and Industrial matters already included therein, such as those related to Combat Arms Earplugs).

Corporate and Unallocated

Corporate and Unallocated operating income includes “corporate special items” and “other corporate expense-net”. Corporate special items include net costs for significant litigation associated with PFAS-related other environmental matters (see Note 14), gain/loss on sale of businesses (see Note 3), and divestiture-related restructuring costs. Other corporate expense-net includes items such as net costs related to limited unallocated corporate staff and centrally managed material resource centers of expertise costs, corporate philanthropic activity, and other net costs that 3M may choose not to allocate directly to its business segments. Other corporate expense-net also includes costs and income from contract manufacturing, transition services and other arrangements with the acquirer of the former Drug Delivery business following its 2020 divestiture. Items classified as revenue from this activity are included in Corporate and Unallocated net sales. Because Corporate and Unallocated includes a variety of miscellaneous items, it is subject to fluctuation on a quarterly and annual basis.