Debt Issuance Costs, Senior Notes, Gross

No definition available.

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- Definition

The leverage ratio as defined in the credit agreement.

+ References

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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Period Type:	instant

- Definition

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

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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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- Definition

Amount, before accumulated amortization, of debt issuance costs related to line of credit arrangements. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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- Definition

The effective interest rate during the reporting period.

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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- Definition

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

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- Definition

Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

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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.

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- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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Long-Term Debt (Details) - USD ($) $ in Millions	12 Months Ended
Long-Term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Nov. 22, 2019
Debt Instrument [Line Items]
Write-off of loan costs	$ 0.0	$ 18.9	$ 0.0
Leverage Ratio	1,140,000
Letters of Credit Outstanding, Amount	$ 4.0	3.9
Senior Notes	550.0	550.0		$ 550.0
Long-term Debt, Gross	1,040.8	1,040.8
Unamortized Debt Issuance Expense	(7.4)	(8.5)
Long-term Debt	1,033.4	1,032.3
Letters of Credit Outstanding, Amount	4.0	3.9
Debt Issuance Costs, Gross				9.1
Write-off of loan costs	$ 0.0	18.9	$ 0.0
Debt Issuance Costs, Line of Credit Arrangements, Gross				0.5
Leverage Ratio	1,140,000
$490.8 Million Term B Loan Facility, due April 2025 [Domain]
Debt Instrument [Line Items]
Secured Debt	$ 490.8	490.8
Secured Debt	$ 490.8	$ 490.8
$490.8 Million Term B Loan Facility, due April 2025 [Domain] \| bank base rate [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.75%
Basis spread on variable rate borrowings	0.75%
$250 Million Revolving Credit Facility, Due November 2024 [Member]
Debt Instrument [Line Items]
Secured Debt				250.0
Secured Debt				$ 250.0
Senior Notes
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage				4.625%
Debt Instrument, Interest Rate, Stated Percentage				4.625%
Debt Issuance Costs, Senior Notes, Gross				$ 8.6
LIBOR [Member] \| $490.8 Million Term B Loan Facility, due April 2025 [Domain]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.75%
Basis spread on variable rate borrowings	1.75%
Minimum [Member] \| $250 Million Revolving Credit Facility, Due November 2024 [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.25%
Basis spread on variable rate borrowings	1.25%
Minimum [Member] \| $250 Million Revolving Credit Facility, Due November 2024 [Member] \| bank base rate [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.25%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.20%
Basis spread on variable rate borrowings	0.25%
Revolving credit facility, unused portion, commitment fee percentage	0.20%
Maximum [Member] \| $490.8 Million Term B Loan Facility, due April 2025 [Domain]
Debt Instrument [Line Items]
Line of Credit Facility, Interest Rate During Period	1.90%
Line of Credit Facility, Interest Rate During Period	1.90%
Maximum [Member] \| $250 Million Revolving Credit Facility, Due November 2024 [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	2.25%
Basis spread on variable rate borrowings	2.25%
Maximum [Member] \| $250 Million Revolving Credit Facility, Due November 2024 [Member] \| bank base rate [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.25%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.35%
Basis spread on variable rate borrowings	1.25%
Revolving credit facility, unused portion, commitment fee percentage	0.35%