Derivative Financial Instruments - Average USD Fair Value Measurements for Contracts Rates (Details)	Sep. 27, 2020
USD:PESO Contract Rate [Member]
Contract rate	24.96%
USD:PESO Mark-to-market Rate [Member]
Mark-to-market rate	22.69%

Market to market average stated rate on a group of interest rate forward or futures contracts.

No definition available.

Name:	smtx_DerivativeAverageMarketToMarketForwardInterestRate
Namespace Prefix:	smtx_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant