Shareholder Report, Average Annual Return (Details)	12 Months Ended	60 Months Ended	120 Months Ended
Shareholder Report, Average Annual Return (Details)	Jan. 31, 2026	Jan. 31, 2026	Jan. 31, 2026
C000121123_1_BBIndexMember_1YRMember
Average Annual Return [Line Items]
Average Annual Return, Percent	16.35%
C000121123_1_BBIndexMember_5YRMember
Average Annual Return [Line Items]
Average Annual Return, Percent		14.99%
C000121123_1_BBIndexMember_10YRMember
Average Annual Return [Line Items]
Average Annual Return, Percent			15.57%
C000121123_NoLoadClassMember_1YRMember
Average Annual Return [Line Items]
Average Annual Return, Percent	11.63%
C000121123_NoLoadClassMember_5YRMember
Average Annual Return [Line Items]
Average Annual Return, Percent		11.64%
C000121123_NoLoadClassMember_10YRMember
Average Annual Return [Line Items]
Average Annual Return, Percent			11.00%
C000121123_0_AdditionalIndexMember_1YRMember
Average Annual Return [Line Items]
Average Annual Return, Percent	13.93%
C000121123_0_AdditionalIndexMember_5YRMember
Average Annual Return [Line Items]
Average Annual Return, Percent		8.61%
C000121123_0_AdditionalIndexMember_10YRMember
Average Annual Return [Line Items]
Average Annual Return, Percent			8.40%