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

No definition available.

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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.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Incremental percentage increase (decrease) in the stated rate on a debt instrument.

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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.

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No definition available.

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Face (par) amount of the original debt instrument that was repurchased.

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No definition available.

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Gross amount of debt extinguished.

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No definition available.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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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.

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Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Cash received on stock transaction after deduction of issuance costs.

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Number of new stock issued during the period.

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Debt Instrument, Covenant, Leverage Ratio, Maximum

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Debt Instrument, Covenant, Threshold Draws On Line Of Credit To Trigger Springing Financial Covenant

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Gain (Loss) On Extinguishment Of Debt, Including Write-Off Of Unamortized Issuance Costs And Prepayment Penalty

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No definition available.

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Financing Arrangements - Narrative (Details) - USD ($)					3 Months Ended	9 Months Ended		12 Months Ended
Financing Arrangements - Narrative (Details) - USD ($)	Jun. 17, 2020	Jun. 08, 2020	Feb. 19, 2020	Feb. 01, 2019	Sep. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Debt Instrument [Line Items]
Prepayment of aggregate principal amount						$ 510,900,000	$ 647,600,000
Aggregate principal amount outstanding					$ 756,400,000	756,400,000
Loss on extinguishment of debt						$ 14,900,000	$ 9,400,000
Redeemable Series A Preferred Units
Debt Instrument [Line Items]
Stock issued (in shares)				51,750,000
Sale of stock in connection with the acquisition of Pre-Acquisition ZI \| Redeemable Series A Preferred Units
Debt Instrument [Line Items]
Proceeds, net of issuance costs				$ 200,200,000
Revolving Credit Facility
Debt Instrument [Line Items]
Basis spread on variable rate						3.50%		3.50%
Effective interest rate		3.70%
Maximum borrowing capacity				100,000,000.0
Extinguishment of debt		$ 35,000,000.0
Draws on revolving credit loan which trigger springing financial covenant (more than)					35,000,000.0	$ 35,000,000.0
Term Loan \| First Lien Term Loan
Debt Instrument [Line Items]
Face amount of debt				965,000,000
Basis spread on variable rate						3.75%		3.75%
Prepayment of aggregate principal amount	$ 101,200,000				100,000,000.0
Repurchased face amount	100,000,000.0
Accrued interest	$ 1,200,000
Aggregate principal amount outstanding					$ 756,400,000	$ 756,400,000
Effective interest rate					4.30%	4.30%		7.50%
Net leverage ratio (not to exceed)					7.65	7.65
Term Loan \| First Lien Term Loan \| LIBOR
Debt Instrument [Line Items]
Decrease to interest rate			0.50%
Basis spread on variable rate			4.00%
Term Loan \| First Lien Term Loan \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate			3.75%
Term Loan \| First Lien Term Loan \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate			4.00%
Term Loan \| First Lien Term Loan \| Base Rate \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate			2.75%
Term Loan \| First Lien Term Loan \| Base Rate \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate			3.00%
Term Loan \| Second Lien Term Loan
Debt Instrument [Line Items]
Face amount of debt				$ 370,000,000
Basis spread on variable rate						8.50%		8.50%
Prepayment of aggregate principal amount		380,600,000
Accrued interest		$ 6,900,000
Effective interest rate		10.80%						11.90%
Prepayment premiums		$ 3,700,000
Loss on extinguishment of debt		7,300,000
Write-off of unamortized issuance costs and prepayment penalty incurred		$ 11,000,000.0