Average Annual Total Returns - FidelityMagellanFund-KPRO - FidelityMagellanFund-KPRO - Fidelity Magellan Fund	May 30, 2024
Fidelity Magellan Fund - Class K \| Return Before Taxes
Average Annual Return:
Past 1 year	31.05%
Past 5 years	15.41%
Past 10 years	11.86%
SP001
Average Annual Return:
Past 1 year	26.29%
Past 5 years	15.69%
Past 10 years	12.03%

Return Before Taxes.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form N-1A
-Section 4
-Subsection b
-Paragraph 2
-Subparagraph iii
-Clause 1
-Exhibit 2

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Namespace Prefix:	rr_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration