Average Annual Total Returns - FidelityMagellanFund-KPRO - FidelityMagellanFund-KPRO - Fidelity Magellan Fund	May 28, 2022
Fidelity Magellan Fund - Class K \| Return Before Taxes
Average Annual Return:
Past 1 year	26.98%
Past 5 years	20.70%
Past 10 years	17.78%
SP001
Average Annual Return:
Past 1 year	28.71%
Past 5 years	18.47%
Past 10 years	16.55%

Return Before Taxes.

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

Name:	rr_AverageAnnualReturnYear01
Namespace Prefix:	rr_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration