Represents the age of employees to be eligible to participate in the defined contribution plan.

No definition available.

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- Definition

Represents employee contributions to a defined contribution pension plan as a percentage of annual base compensation.

+ References

No definition available.

+ Details

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- Definition

The percentage of the employee contribution for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

Defined Contribution Plan Employer Discretionary Matching Contribution Percent

+ References

No definition available.

+ Details

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Namespace Prefix:	ssb_
Data Type:	xbrli:pureItemType
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- References

No definition available.

+ Details

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- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

+ Details

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Period Type:	duration

- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

+ Details

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- Details

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Namespace Prefix:
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- Details

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Retirement Plans - Safe Harbor plan (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2018
Employees' savings plan
Matching contribution by the company (as a percent)			100.00%
Expenses recognized under 401(K) plan	$ 1.9	$ 1.2
Discretionary matching contribution	0.375		2
Minimum
Employees' savings plan
Age of employees to be eligible to participate in the defined contribution plan	21 years
Percentage of annual base compensation that participants may elect to contribute	1.00%
Maximum
Employees' savings plan
Percentage of annual base compensation that participants may elect to contribute	50.00%
Percentage of employees salary for which the company contributes a matching contribution			4.00%