The Company and Summary of Significant Accounting Policies - Narrative (Details)	3 Months Ended
	Dec. 31, 2021
Adevinta
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Ownership percentage after sale	33.00%
Gmarket
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Ownership percentage after sale	19.99%
Discontinued Operations, Disposed of by Sale | eBay Korea
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Percentage of outstanding equity interests sold	80.01%