Earnings per share (Details) ¥ / shares in Units, $ / shares in Units, ¥ in Millions, shares in Millions, $ in Millions	12 Months Ended
Mar. 31, 2019 USD ($) $ / shares shares	Mar. 31, 2019 CNY (¥) ¥ / shares shares	Mar. 31, 2018 CNY (¥) ¥ / shares shares	Mar. 31, 2017 CNY (¥) ¥ / shares shares
Numerator:
Net income attributable to ordinary shareholders for computing net income per ordinary share - basic	$ 13,053	¥ 87,600	¥ 63,985	¥ 43,675
Dilution effect arising from share-based awards issued by a subsidiary and equity investees \| ¥		(42)	(21)	(11)
Net income attributable to ordinary shareholders for computing net income per ordinary share - diluted \| ¥		¥ 87,558	¥ 63,964	¥ 43,664
Shares (denominator):
Weighted average number of shares used in calculating net income per ordinary share - basic (million shares)	2,580	2,580	2,553	2,493
Adjustments for dilutive RSUs and share options (million shares)	43	43	57	80
Weighted average number of shares used in calculating net income per ordinary share - diluted (million shares)	2,623	2,623	2,610	2,573
Net income per ordinary share/ADS - basic \| (per share)	$ 5.06	¥ 33.95	¥ 25.06	¥ 17.52
Net income per ordinary share/ADS - diluted \| (per share)	$ 4.97	¥ 33.38	¥ 24.51	¥ 16.97

Amount of increase (decrease) to net income used for calculating diluted earnings per share (EPS), resulting from the assumed exercise of stock options or restrictive stock units (RSUs).

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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