Share-Based Payments - Narrative (Detail) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for award		248,000,000
Compensation cost recognized/(reduced), pre-tax		$ 525	$ 872	$ 1,200
Tax benefit for share-based compensation expense		$ 93	160	227
Seagen [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for award		68,000,000
2019 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of additional shares authorized		400,000,000
Award requisite service period		36 months
Maximum shares available per individual during the plan period		20,000,000
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted in period (in shares)		10,007,000
Compensation cost recognized/(reduced), pre-tax		$ 437	402	281
Restricted Stock Units (RSUs) [Member] | 2019 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares counted toward maximum		3
Portfolio Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted in period (in shares)	[1]	8,751,000
Compensation cost recognized/(reduced), pre-tax		$ (138)	144	535
Portfolio Performance Shares [Member] | 2019 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares counted toward maximum		3
Performance Share Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted in period (in shares)		1,623,000
Award requisite service period		3 years
Compensation cost recognized/(reduced), pre-tax		$ (5)	73	76
Performance Share Awards [Member] | 2019 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares counted toward maximum		3
Breakthrough Performance Awards (BPAs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted in period (in shares)		0
Number of shares outstanding (in shares)		0
Award requisite service period		1 year
Breakthrough Performance Awards (BPAs) [Member] | 2019 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares counted toward maximum		3
Total Shareholder Return Units (TSRUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted in period (in shares)		26,631,000
Number of shares outstanding (in shares)	[2],[3]	163,572,000
Compensation cost recognized/(reduced), pre-tax		$ 244	255	259
Total Shareholder Return Units (TSRUs) [Member] | 2019 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares counted toward maximum		1
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost recognized/(reduced), pre-tax		$ 4	$ 4	$ 5
Stock Options [Member] | 2019 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares counted toward maximum		1

[1] Vested and non-vested shares outstanding, but not paid as of December 31, 2023 were 35.8 million.

[2] In 2023, 1,827,019 TSRUs with a weighted-average grant price of $31.73 per unit were converted into 679,742 PTUs.

[3] In 2023, we settled 38,957,175 TSRUs with a weighted-average grant price of $29.80 per unit.