Stockholders' equity (Details Textual) (Details) $ / shares in Units, shares in Millions, $ in Millions				1 Months Ended			3 Months Ended				6 Months Ended
	Sep. 08, 2022 $ / shares	Aug. 03, 2022 $ / shares	Feb. 25, 2022 USD ($) shares	Jun. 30, 2022 USD ($) $ / shares	Mar. 31, 2022 $ / shares	Dec. 31, 2021 $ / shares	Jun. 30, 2022 USD ($) shares	Mar. 31, 2022 USD ($) $ / shares shares	Jun. 30, 2021 USD ($) shares	Mar. 31, 2021 USD ($) $ / shares shares	Jun. 30, 2022 USD ($) shares	Jun. 30, 2021 USD ($) shares	Feb. 24, 2022 financial_institution
Class of Stock [Line Items]
Stock repurchased, Shares | shares							0.0	24.6	6.5	3.7	24.6	10.2
Stock repurchased							$ 0	$ 5,410	$ 1,592	$ 865	$ 5,410	$ 2,457
Repurchases of common stock								$ 6,310	1,592	$ 865
Amount available for stock repurchases under a board approved stock repurchase plan				$ 4,600			$ 4,600				$ 4,600
Dividends declared per share (in usd per share) | $ / shares					$ 1.94	$ 1.94		$ 1.94		$ 1.76
Dividends paid per share (in usd per share) | $ / shares				$ 1.94	$ 1.94
Subsequent Event [Member]
Class of Stock [Line Items]
Dividends declared per share (in usd per share) | $ / shares		$ 1.94
Accumulated deficit [Member]
Class of Stock [Line Items]
Repurchases of common stock								$ 5,410	$ 1,592	$ 865
Common stock and additional paid-in capital [Member]
Class of Stock [Line Items]
Repurchases of common stock								$ 900
Accelerated stock repurchase agreement
Class of Stock [Line Items]
Stock repurchased, Shares | shares			23.3
Stock repurchased			$ 6,000
Number of Third-Party Financial Institutions | financial_institution													3
Accelerated stock repurchase agreement | Accumulated deficit [Member]
Class of Stock [Line Items]
Repurchases of common stock			5,100
Accelerated stock repurchase agreement | Common stock and additional paid-in capital [Member]
Class of Stock [Line Items]
Repurchases of common stock			$ 900
Forecast [Member]
Class of Stock [Line Items]
Dividends paid per share (in usd per share) | $ / shares	$ 1.94