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

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

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

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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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Weighted average interest rate of debt outstanding.

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Fixed interest rate related to the interest rate derivative.

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Variable interest rate in effect as of the balance sheet date related to the interest rate derivative.

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- Definition

Amount of liability hedged in fair value hedging relationship.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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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, 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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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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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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Debt - Narrative (Details) - USD ($)		3 Months Ended	8 Months Ended	9 Months Ended
Debt - Narrative (Details) - USD ($)	Apr. 01, 2019	Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2019	Sep. 30, 2018	Jun. 15, 2018	May 18, 2018	May 11, 2018
Debt Instrument
Total debt		$ 230,200,000	$ 192,700,000	$ 230,200,000
Repayments of debt				22,200,000	$ 11,200,000
Other Operations
Debt Instrument
Face amount		$ 11,200,000	0	$ 11,200,000
Effective percentage		9.60%		9.60%
Unamortized issuance cost		$ (400,000)	0	$ (400,000)
MediaAlpha
Debt Instrument
Total debt		0	14,200,000	0
MediaAlpha \| MediaAlpha Bank Facility
Debt Instrument
Total debt		0	14,200,000	0
Face amount		0	$ 14,300,000	0
Effective percentage			7.10%
Unamortized issuance cost		0	$ (100,000)	0
NSM Holding Co LLC
Debt Instrument
Total debt		219,400,000	178,500,000	219,400,000
NSM Holding Co LLC \| NSM Bank Facility
Debt Instrument
Total debt		217,700,000	176,600,000	217,700,000
Face amount								$ 100,000,000.0
Term Loan \| NSM Holding Co LLC \| NSM Bank Facility
Debt Instrument
Total debt		221,800,000		221,800,000
Face amount		$ 221,800,000	$ 180,400,000	$ 221,800,000			$ 51,000,000.0	224,000,000.0
Effective percentage		7.70%	7.40%	7.70%
Unamortized issuance cost		$ (4,100,000)	$ (3,800,000)	$ (4,100,000)
Repayments of debt		500,000		1,400,000
Proceeds from borrowings				42,900,000
Term Loan \| NSM Holding Co LLC \| Other Operations
Debt Instrument
Total debt		1,700,000	1,900,000	1,700,000
Unamortized issuance cost		(0.025)	$ (0.022)	(0.025)
Revolving Credit Facility \| NSM Holding Co LLC \| NSM Bank Facility
Debt Instrument
Total commitment under revolving credit facility								10,000,000.0
Borrowings under facility								$ 2,000,000.0
Repayments of debt		$ 6,500,000
Proceeds from borrowings				$ 6,500,000
Interest Rate Swap \| NSM Holding Co LLC
Debt Instrument
Derivative, fixed interest rate						2.97%
Derivative, variable interest rate		2.11%		2.11%
Interest Rate Swap \| Term Loan \| NSM Holding Co LLC \| NSM Bank Facility
Debt Instrument
Total debt		$ 149,100,000		$ 149,100,000
Total commitment under revolving credit facility						$ 151,000,000.0
Hedged Liability, Fair Value Hedge						$ 151,000,000.0
Derivative, fixed interest rate		2.97%		2.97%
Debt, weighted average interest rate, all-in		7.17%		7.17%
London Interbank Offered Rate (LIBOR) \| Minimum \| Term Loan \| NSM Holding Co LLC \| NSM Bank Facility
Debt Instrument
Basis spread on variable rate		4.25%	4.25%
London Interbank Offered Rate (LIBOR) \| Maximum \| Term Loan \| NSM Holding Co LLC \| NSM Bank Facility
Debt Instrument
Basis spread on variable rate		4.75%	4.75%
Prime Rate \| Minimum \| Term Loan \| NSM Holding Co LLC \| NSM Bank Facility
Debt Instrument
Basis spread on variable rate		3.25%	3.25%
Prime Rate \| Maximum \| Term Loan \| NSM Holding Co LLC \| NSM Bank Facility
Debt Instrument
Basis spread on variable rate		3.75%	3.75%
Designated as Hedging Instrument \| Interest Rate Swap \| Term Loan \| NSM Holding Co LLC \| NSM Bank Facility
Debt Instrument
Total debt		$ 149,100,000		$ 149,100,000
Debt, weighted average interest rate, all-in		7.47%		7.47%
Not Designated as Hedging Instrument \| Interest Rate Swap \| Term Loan \| NSM Holding Co LLC \| NSM Bank Facility
Debt Instrument
Total debt		$ 72,700,000		$ 72,700,000
Effective percentage		7.12%		7.12%
Embrace \| NSM Holding Co LLC
Debt Instrument
Proceeds from borrowings	$ 20,400,000
Embrace \| Term Loan \| NSM Holding Co LLC \| NSM Bank Facility
Debt Instrument
Proceeds from borrowings				$ 20,400,000
Carrying Value \| MediaAlpha \| MediaAlpha Bank Facility
Debt Instrument
Total debt		$ 0	$ 14,200,000	0
Carrying Value \| NSM Holding Co LLC \| NSM Bank Facility
Debt Instrument
Total debt		217,700,000	176,600,000	217,700,000
Carrying Value \| Other Operations
Debt Instrument
Total debt		$ 10,800,000	$ 0	10,800,000
Renewal Rights \| Term Loan \| NSM Holding Co LLC \| NSM Bank Facility
Debt Instrument
Proceeds from borrowings				$ 22,500,000