Basis of Presentation, Nature of Operations and Summary of Significant Accounting Policies (Policies)	12 Months Ended
Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	The consolidated financial statements were prepared using accounting principles generally accepted in the United States of America ("GAAP").
Use of Estimates	These principles require us to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities and the reported amounts of revenues and expenses.
Nature of Operations	Nature of Operations We design, develop, market, install, host and support healthcare information technology, healthcare devices, hardware and content solutions for healthcare organizations and consumers. We also provide a wide range of value-added services, including implementation and training, remote hosting, operational management services, revenue cycle services, support and maintenance, healthcare data analysis, clinical process optimization, transaction processing, employer health centers, and data-driven services that help life sciences companies with the discovery, development and deployment of therapies.
Fiscal Period	Prior to fiscal year 2020, our fiscal year ended on the Saturday closest to December 31. Fiscal year 2019 consisted of 364 days and ended on December 28, 2019.
Cash Equivalents	Cash Equivalents - Cash equivalents consist of short-term debt securities with original maturities of less than 90 days.
Investments	Investments in Debt Securities – We account for our investments in debt securities as available-for-sale investments in accordance with Accounting Standards Codification Topic ("ASC") 320, Investments-Debt Securities. Short-term available-for-sale investments are primarily invested in time deposits, commercial paper, government and corporate bonds, with maturities of less than one year. Long-term available-for-sale investments are primarily invested in government and corporate bonds with maturities of less than two years. Available-for-sale investments are recorded at fair value with the unrealized gains and losses reflected in accumulated other comprehensive loss until realized. Realized gains and losses from the sale of available-for-sale investments, if any, are determined on a specific identification basis. Generally, premiums are amortized and discounts are accreted over the life of the security as adjustments to interest income for our investments. For investments in callable debt securities, any premiums are amortized to the earliest call date. Interest income is recognized when earned. Refer to Note (4) and Note (12) for further description of these assets and their fair value. (c) Investments in Equity Securities - We account for our investments in equity securities that give us the ability to exercise significant influence over the operating and financial policies of an investee under the equity method in accordance with ASC 323, Investments-Equity Method and Joint Ventures. Under the equity method, we recognize our share of the earnings or losses of an investee, generally on a three-month lag. Such share of the investee's earnings or losses are presented in "Other income (loss), net" in our consolidated statements of operations. We account for our investments in equity securities that do not qualify for equity method accounting in accordance with ASC 321, Investments-Equity Securities ("ASC 321"). We measure these investments at fair value with changes in fair value recognized in "Other income (loss), net" in our consolidated statements of operations for such investments with readily determinable fair values. For these investments that do not have readily determinable fair values, we measure such investments at cost minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or similar investment of the same issuer.
Concentrations	Concentrations - The majority of our cash and cash equivalents are held at three major financial institutions. Deposits held with banks may exceed the amount of insurance provided on such deposits. Generally these deposits may be redeemed upon demand.
Inventory	Inventory - Inventory consists primarily of computer hardware and sublicensed software, held for resale. Inventory is recorded at the lower of cost (first-in, first-out) or net realizable value.
Property and Equipment	Property and Equipment - We account for property and equipment in accordance with ASC 360, Property, Plant, and Equipment. Property, equipment and leasehold improvements are stated at cost. Depreciation of property and equipment is computed using the straight-line method over periods of one to 50 years. Amortization of leasehold improvements is computed using a straight-line method over the shorter of the lease terms or the useful lives, which range from periods of one to 15 years.
Goodwill	Goodwill - We account for goodwill under the provisions of ASC 350, Intangibles – Goodwill and Other. Goodwill is not amortized but is evaluated for impairment annually or whenever there is an impairment indicator. All goodwill is assigned to a reporting unit, where it is subject to an annual impairment assessment. Based on these evaluations, there was no impairment of goodwill in 2021, 2020 or 2019. Refer to Note (10) for more information on goodwill and other intangible assets.
Intangible Assets	Intangible Assets - We account for intangible assets in accordance with ASC 350, Intangibles – Goodwill and Other. Amortization of finite-lived intangible assets is computed using the straight-line method over periods of three to 30 years.
Income Taxes	Income Taxes - Income taxes are accounted for in accordance with ASC 740, Income Taxes. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. Refer to Note (14) for additional information regarding income taxes.
Earnings per Common Share	Earnings per Common Share - Basic earnings per share ("EPS") excludes dilution and is computed, in accordance with ASC 260, Earnings Per Share, by dividing income available to common shareholders by the weighted-average number of common shares outstanding for the period. Diluted EPS reflects the potential dilution that could occur if securities or other contracts to issue stock were exercised or converted into common stock or resulted in the issuance of common stock that then shared in our earnings. Refer to Note (15) for additional details of our earnings per share computations.
Accounting for Share-based Payments	Accounting for Share-based Payments - We recognize all share-based payments to associates, directors and consultants, including grants of stock options, restricted stock, restricted stock units and performance shares, in the financial statements as compensation cost based on their fair value on the date of grant, in accordance with ASC 718, Compensation-Stock Compensation. This compensation cost is recognized over the vesting period on a straight-line basis for the fair value of awards that actually vest. Refer to Note (16) for a detailed discussion of share-based payments.
Postemployment Benefit Plans	Voluntary Separation Benefits - We account for voluntary separation benefits in accordance with the provisions of ASC 712, Compensation-Nonretirement Postemployment Benefits. Voluntary separation benefits are recorded to expense when an associate irrevocably accepts the offer and the amount of the termination liability is reasonably estimable.In 2021, 2020 and 2019, we recognized $53 million, $20 million and $52 million, respectively, of expenses in connection with voluntary separation benefits, which are included in "General and administrative" expense in our consolidated statements of operations.
Costs Associated with Exit or Disposal Activities or Restructurings	Exit or Disposal Cost Obligations - We account for involuntary employee separation benefits pursuant to one-time benefit arrangements and contract termination costs in accordance with ASC 420, Exit or Disposal Cost Obligations.In 2021, 2020 and 2019, we recognized $56 million, $22 million and $34 million, respectively, of expenses in connection with involuntary associate termination events, which are included in "General and administrative" expense in our consolidated statements of operations.In 2020 and 2019, we recognized $29 million and $66 million, respectively, of pre-tax charges within our Domestic segment in connection with the termination of certain contracts prior to the end of their stated terms. Such charges are included in "Sales and client service" expense in our consolidated statements of operations.
Foreign Currency	Foreign Currency - In accordance with ASC 830, Foreign Currency Matters, assets and liabilities of non-U.S. subsidiaries whose functional currency is the local currency are translated into U.S. dollars at exchange rates prevailing at the balance sheet date. Revenues and expenses are translated at average exchange rates during the year. The net exchange differences resulting from these translations are reported in accumulated other comprehensive loss. Gains and losses resulting from foreign currency transactions are included in the consolidated statements of operations.

Basis of Presentation, Nature of Operations and Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2021

Organization, Consolidation and Presentation of Financial Statements [Abstract]

The consolidated financial statements were prepared using accounting principles generally accepted in the United States of America ("GAAP").

Use of Estimates

These principles require us to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities and the reported amounts of revenues and expenses.

Nature of Operations

We design, develop, market, install, host and support healthcare information technology, healthcare devices, hardware and content solutions for healthcare organizations and consumers. We also provide a wide range of value-added services, including implementation and training, remote hosting, operational management services, revenue cycle services, support and maintenance, healthcare data analysis, clinical process optimization, transaction processing, employer health centers, and data-driven services that help life sciences companies with the discovery, development and deployment of therapies.

Fiscal Period

Prior to fiscal year 2020, our fiscal year ended on the Saturday closest to December 31. Fiscal year 2019 consisted of 364 days and ended on December 28, 2019.

Cash Equivalents

Cash Equivalents - Cash equivalents consist of short-term debt securities with original maturities of less than 90 days.

Investments

Investments in Debt Securities – We account for our investments in debt securities as available-for-sale investments in accordance with Accounting Standards Codification Topic ("ASC") 320, Investments-Debt Securities. Short-term available-for-sale investments are primarily invested in time deposits, commercial paper, government and corporate bonds, with maturities of less than one year. Long-term available-for-sale investments are primarily invested in government and corporate bonds with maturities of less than two years.

Available-for-sale investments are recorded at fair value with the unrealized gains and losses reflected in accumulated other comprehensive loss until realized. Realized gains and losses from the sale of available-for-sale investments, if any, are determined on a specific identification basis.

Generally, premiums are amortized and discounts are accreted over the life of the security as adjustments to interest income for our investments. For investments in callable debt securities, any premiums are amortized to the earliest call date. Interest income is recognized when earned.

Refer to Note (4) and Note (12) for further description of these assets and their fair value.

(c) Investments in Equity Securities - We account for our investments in equity securities that give us the ability to exercise significant influence over the operating and financial policies of an investee under the equity method in accordance with ASC 323, Investments-Equity Method and Joint Ventures. Under the equity method, we recognize our share of the earnings or losses of an investee, generally on a three-month lag. Such share of the investee's earnings or losses are presented in "Other income (loss), net" in our consolidated statements of operations.

We account for our investments in equity securities that do not qualify for equity method accounting in accordance with ASC 321, Investments-Equity Securities ("ASC 321"). We measure these investments at fair value with changes in fair value recognized in "Other income (loss), net" in our consolidated statements of operations for such investments with readily determinable fair values. For these investments that do not have readily determinable fair values, we measure such investments at cost minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or similar investment of the same issuer.

Concentrations

Concentrations - The majority of our cash and cash equivalents are held at three major financial institutions. Deposits held with banks may exceed the amount of insurance provided on such deposits. Generally these deposits may be redeemed upon demand.

Inventory

Inventory - Inventory consists primarily of computer hardware and sublicensed software, held for resale. Inventory is recorded at the lower of cost (first-in, first-out) or net realizable value.

Property and Equipment

Property and Equipment - We account for property and equipment in accordance with ASC 360, Property, Plant, and Equipment. Property, equipment and leasehold improvements are stated at cost. Depreciation of property and equipment is computed using the straight-line method over periods of one to 50 years. Amortization of leasehold improvements is computed using a straight-line method over the shorter of the lease terms or the useful lives, which range from periods of one to 15 years.

Goodwill

Goodwill - We account for goodwill under the provisions of ASC 350, Intangibles – Goodwill and Other. Goodwill is not amortized but is evaluated for impairment annually or whenever there is an impairment indicator. All goodwill is assigned to a reporting unit, where it is subject to an annual impairment assessment. Based on these evaluations, there was no impairment of goodwill in 2021, 2020 or 2019. Refer to Note (10) for more information on goodwill and other intangible assets.

Intangible Assets

Intangible Assets - We account for intangible assets in accordance with ASC 350, Intangibles – Goodwill and Other. Amortization of finite-lived intangible assets is computed using the straight-line method over periods of three to 30 years.

Income Taxes

Income Taxes - Income taxes are accounted for in accordance with ASC 740, Income Taxes. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. Refer to Note (14) for additional information regarding income taxes.

Earnings per Common Share

Earnings per Common Share - Basic earnings per share ("EPS") excludes dilution and is computed, in accordance with ASC 260, Earnings Per Share, by dividing income available to common shareholders by the weighted-average number of common shares outstanding for the period. Diluted EPS reflects the potential dilution that could occur if securities or other contracts to issue stock were exercised or converted into common stock or resulted in the issuance of common stock that then shared in our earnings. Refer to Note (15) for additional details of our earnings per share computations.

Accounting for Share-based Payments

Accounting for Share-based Payments - We recognize all share-based payments to associates, directors and consultants, including grants of stock options, restricted stock, restricted stock units and performance shares, in the financial statements as compensation cost based on their fair value on the date of grant, in accordance with ASC 718, Compensation-Stock Compensation. This compensation cost is recognized over the vesting period on a straight-line basis for the fair value of awards that actually vest. Refer to Note (16) for a detailed discussion of share-based payments.

Postemployment Benefit Plans

Voluntary Separation Benefits - We account for voluntary separation benefits in accordance with the provisions of ASC 712, Compensation-Nonretirement Postemployment Benefits. Voluntary separation benefits are recorded to expense when an associate irrevocably accepts the offer and the amount of the termination liability is reasonably estimable.In 2021, 2020 and 2019, we recognized $53 million, $20 million and $52 million, respectively, of expenses in connection with voluntary separation benefits, which are included in "General and administrative" expense in our consolidated statements of operations.

Costs Associated with Exit or Disposal Activities or Restructurings

Exit or Disposal Cost Obligations - We account for involuntary employee separation benefits pursuant to one-time benefit arrangements and contract termination costs in accordance with ASC 420, Exit or Disposal Cost Obligations.In 2021, 2020 and 2019, we recognized $56 million, $22 million and $34 million, respectively, of expenses in connection with involuntary associate termination events, which are included in "General and administrative" expense in our consolidated statements of operations.In 2020 and 2019, we recognized $29 million and $66 million, respectively, of pre-tax charges within our Domestic segment in connection with the termination of certain contracts prior to the end of their stated terms. Such charges are included in "Sales and client service" expense in our consolidated statements of operations.

Foreign Currency

Foreign Currency - In accordance with ASC 830, Foreign Currency Matters, assets and liabilities of non-U.S. subsidiaries whose functional currency is the local currency are translated into U.S. dollars at exchange rates prevailing at the balance sheet date. Revenues and expenses are translated at average exchange rates during the year. The net exchange differences resulting from these translations are reported in accumulated other comprehensive loss. Gains and losses resulting from foreign currency transactions are included in the consolidated statements of operations.