Share Based Compensation - Summary of Stock Purchase Plans (Detail) - Ericsson Share Purchase Plan [Member]	12 Months Ended
Dec. 31, 2024 Employee Country	Dec. 31, 2023 Country
Disclosure Of Detailed Information About Stock Purchase Plans [Line Items]
Number of participants \| Employee	13,148
Take-up rate – percent of eligible employees	17.30%
Number of countries launched the plan \| Country	69	69

Disclosure of detailed information about stock purchase plans.

No definition available.

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