It represents the percentage rate of capital conservation buffer.

No definition available.

Name:	fsfg_CapitalConservationBufferpercentage
Namespace Prefix:	fsfg_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Regulatory Capital (Additional Information) (Detail)	Sep. 30, 2019	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Capital Conservation Buffer, Percentage			0.625%	0.00%
Scenario, Forecast [Member]
Capital Conservation Buffer, Percentage	2.50%	1.25%