Commitments and Contingencies - Employee Relations (Details)	12 Months Ended
Dec. 31, 2018
Collective bargaining arrangements
Percentage of employees represented by labor unions	14.00%

Represents the percentage of employees who are represented by labor unions.

No definition available.

Name:	ssd_PercentageOfEmployeesAsRepresentedByLaborUnions
Namespace Prefix:	ssd_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration