Goodwill and Other Intangible Assets - Additional Information (Details)	9 Months Ended
Jun. 30, 2018
Goodwill And Intangible Assets Disclosure [Abstract]
Projection period for discounted cash flow analyses to estimate reporting unit fair value	10 years

The length in years of the projection period used in estimating the fair value of the reporting unit using discounted cash flow analyses.

No definition available.

Name:	sph_ProjectionPeriodForDiscountedCashFlowAnalysesToEstimateReportingUnitFairValue
Namespace Prefix:	sph_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration