Obligations under Finance Leases - Additional Information (Detail) ¥ in Millions	Jan. 01, 2019 CNY (¥)
Increase (decrease) due to application of IFRS 16 [member]
Disclosure of finance lease and operating lease by lessee [line items]
Obligations Under Finance Lease Liabilities	¥ 72,221

The present value of minimum finance lease payments payable. [Refer: Minimum finance lease payments payable]

No definition available.

Name:	znh_ObligationsUnderFinanceLeases
Namespace Prefix:	znh_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant