Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ 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 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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FAIR VALUE MEASUREMENT - Schedule of fair values of debt obligations (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020	Dec. 15, 2020	Jan. 12, 2017
Debt
Debt obligations	$ 1,298.5	$ 1,319.1
Level 2
Debt
Debt obligations	1,298.5	1,319.1
Term Loan Agreement \| Level 2
Debt
Debt obligations	$ 160.8	$ 70.0
3.650% Senior Notes
Debt
Interest rate (as a percent)	3.65%	3.65%	3.65%	3.65%
3.650% Senior Notes \| Level 2
Debt
Debt obligations	$ 725.4	$ 744.0
1.625% Senior Notes
Debt
Interest rate (as a percent)	1.625%	1.625%	1.625%
1.625% Senior Notes \| Level 2
Debt
Debt obligations	$ 482.5	$ 505.1