Revenue - Schedule of Contract Liabilities Balances (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Contract Liability Balances with Customer
Balance, beginning of year	$ (17.4)	$ (15.7)
Acquisitions		(1.1)
Additional contract liabilities	(17.5)	(16.4)
Recognition of revenue from contract liabilities	17.4	15.8
Balance, end of year	$ (17.5)	$ (17.4)

Contract liability balances with customer.

No definition available.

Name:	sp_ContractLiabilityBalancesWithCustomerRollForward
Namespace Prefix:	sp_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Contract with customer liability revenue recognized related to acquisition.

+ References

No definition available.

+ Details

Name:	sp_ContractWithCustomerLiabilityRevenueRecognizedRelatedToAcquisition
Namespace Prefix:	sp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Contract with Customer, Liability, Additional Contract Liabilities

+ References

No definition available.

+ Details

Name:	sp_ContractwithCustomerLiabilityAdditionalContractLiabilities
Namespace Prefix:	sp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479837/606-10-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-8

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479837/606-10-45-2

+ Details

Name:	us-gaap_ContractWithCustomerLiabilityCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of increase (decrease) in obligation to transfer good or service to customer for which consideration from customer has been received or is due, from business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-10

+ Details

Name:	us-gaap_ContractWithCustomerLiabilityIncreaseDecreaseForContractAcquiredInBusinessCombination
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration