Line of Credit Facility, Potentially Additional Borrowing Capacity

No definition available.

Name:	core_LineOfCreditFacilityPotentiallyAdditionalBorrowingCapacity
Namespace Prefix:	core_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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

- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

+ Details

Name:	us-gaap_StockRepurchaseProgramAuthorizedAmount1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Period which shares may be purchased under a stock repurchase plan authorized by an entity's Board of Directors, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_StockRepurchaseProgramPeriodInForce1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShareRepurchaseProgramAxis=core_A2020ProgramMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShareRepurchaseProgramAxis=core_A2021ProgramMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Subsequent Events (Details) - USD ($)	1 Months Ended
Subsequent Events (Details) - USD ($)	Feb. 28, 2021	Feb. 26, 2021	Dec. 31, 2020	Feb. 24, 2020
Revolving Credit Facility
Subsequent Event [Line Items]
Revolving credit facility maximum borrowing capacity			$ 750,000,000.0
Revolving credit facility, expansion feature			$ 200,000,000.0
2020 Program
Subsequent Event [Line Items]
Authorized increase to stock repurchase plan				$ 60,000,000.0
Subsequent Event \| Revolving Credit Facility
Subsequent Event [Line Items]
Revolving credit facility maximum borrowing capacity		$ 750,000,000
Revolving credit facility, expansion feature		$ 200,000,000
Subsequent Event \| Shareholder Return Plan
Subsequent Event [Line Items]
Stock repurchase program, period in force	3 years
Authorized increase to stock repurchase plan	$ 375,000,000