Stockholders' Equity - Changes in Stockholders Equity (Details) - USD ($) $ in Millions	3 Months Ended				6 Months Ended		12 Months Ended
	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Changes in Stockholders' Equity
Beginning balance	$ 216,661	$ 201,875	$ 154,526	$ 146,043	$ 201,875	$ 146,043	$ 168,602
Other comprehensive income (loss)	(395)		293		(953)	807
Net income	13,485		6,750		23,916	9,922	44,419	$ 13,072
Ending balance	236,447	216,661	168,602	154,526	236,447	168,602	236,447	168,602
Common stock
Changes in Stockholders' Equity
Beginning balance	109	109	108	108	109	108	108
Stock-based compensation and issuance of employee benefit plan stock	1		0		1	0
Ending balance	110	109	108	108	110	108	110	108
Treasury stock
Changes in Stockholders' Equity
Beginning balance	(7,837)	(7,837)	(7,837)	(7,837)	(7,837)	(7,837)	(7,837)
Ending balance	(7,837)	(7,837)	(7,837)	(7,837)	(7,837)	(7,837)	(7,837)	(7,837)
Additional paid-in capital
Changes in Stockholders' Equity
Beginning balance	103,938	99,025	79,863	75,066	99,025	75,066	86,896
Stock-based compensation and issuance of employee benefit plan stock	6,695		7,033		11,608	11,830
Ending balance	110,633	103,938	86,896	79,863	110,633	86,896	110,633	86,896
Accumulated other comprehensive income (loss)
Changes in Stockholders' Equity
Beginning balance	(3,598)	(3,040)	(3,973)	(4,487)	(3,040)	(4,487)	(3,680)
Other comprehensive income (loss)	(395)		293		(953)	807
Ending balance	(3,993)	(3,598)	(3,680)	(3,973)	(3,993)	(3,680)	(3,993)	(3,680)
Retained earnings
Changes in Stockholders' Equity
Beginning balance	124,049	113,618	86,365	83,193	113,618	83,193	93,115
Net income	13,485		6,750		23,916	9,922
Ending balance	$ 137,534	$ 124,049	$ 93,115	$ 86,365	$ 137,534	$ 93,115	$ 137,534	$ 93,115