Earnings per Share - Schedule of Basic and Diluted Loss Per Share/Common Unit (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Numerator
Net income attributable to Coupang stockholders	$ 208	$ 154	$ 1,360
Denominator
Weighted-average shares used in computing net income per share attributable to Class A and Class B common stockholders, basic (in shares)	1,818	1,794	1,782
Dilutive effect of equity compensation awards (in shares)	37	32	21
Weighted-average shares used in computing net income (loss) per share attributable to Class A and Class B common stockholders, diluted (in shares)	1,855	1,826	1,803
Earnings per share:
Basic (in usd per share)	$ 0.11	$ 0.09	$ 0.76
Diluted (in usd per share)	$ 0.11	$ 0.08	$ 0.75
Anti-dilutive shares	0	1	3