DEBT - Senior Notes (Narrative) (Details)	3 Months Ended
Mar. 31, 2021 USD ($)
2022 Senior Note
Debt Instrument [Line Items]
Debt issuance costs	$ 5,100,000
2025 Senior Notes
Debt Instrument [Line Items]
Deferred issuance costs	$ 7,700
Summit Holdings And Finance Corporation \| 2022 Senior Note
Debt Instrument [Line Items]
Redemption price, expressed as percentage of principal amount	100.00%
Summit Holdings And Finance Corporation \| 2025 Senior Notes \| Redemption period one
Debt Instrument [Line Items]
Redemption price, expressed as percentage of principal amount	104.313%
Summit Holdings And Finance Corporation \| 2025 Senior Notes \| Redemption period two
Debt Instrument [Line Items]
Redemption price, expressed as percentage of principal amount	102.875%
Summit Holdings And Finance Corporation \| 2025 Senior Notes \| Redemption period three
Debt Instrument [Line Items]
Redemption price, expressed as percentage of principal amount	100.00%

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

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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 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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-Section 45
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