Debt and Credit Agreements - Schedule of Long-term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Debt Obligation	$ 1,361,642	$ 1,300,532
Less: deferred financing costs	(18,887)	(15,767)
Total debt obligations, net of deferred financing costs	1,342,755	1,284,765
Current maturities of long-term debt	(9,181)	(13,576)
Long-term debt	1,333,574	1,271,189
Other financing payable (including finance leases) in varying amounts
Debt Instrument [Line Items]
Debt Obligation	24,406	21,344
Term Loan Facility \| New Term Loan
Debt Instrument [Line Items]
Debt Obligation	498,750	0
Term Loan Facility \| Term Loan A
Debt Instrument [Line Items]
Debt Obligation	0	280,000
Term Loan Facility \| Term Loan B
Debt Instrument [Line Items]
Debt Obligation	0	218,188
Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt Obligation	338,486	281,000
Senior Notes \| 5.75% Notes, due July 31, 2027
Debt Instrument [Line Items]
Debt Obligation	$ 500,000	$ 500,000

Debt Long Term and Short Term Less Unamortized Debt Issuance Expense Combined Amount

No definition available.

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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.

+ Details

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- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ 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 210.5-02.19,20)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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

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