Debt Instrument, Discount Percent

No definition available.

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- Definition

Payments for Contributions to Subsidiaries

+ References

No definition available.

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- Definition

Proceeds from Subsidiary Entity, Dividends or Distributions

+ References

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.

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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.

+ Details

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6036836-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399

Reference 3: 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(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

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

+ References

+ Details

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Balance Type:	na
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- Definition

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

+ References

+ Details

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- Definition

The percentage points added to the reference rate to compute the variable rate on the interest rate derivative.

+ References

No definition available.

+ Details

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

+ Details

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- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

+ Details

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Period Type:	instant

- 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

Dividends received on equity and other investments during the current period.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 16
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3337-108585

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- Definition

Indebtedness divided by net capital.

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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Condensed Financial Information of Registrant Condensed Financial Information of Registrant (Narratives) (Details)				12 Months Ended
	Mar. 29, 2017 USD ($)	Mar. 08, 2017 USD ($)	Feb. 13, 2014	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Jul. 31, 2018	Jan. 31, 2018
Condensed Financial Statements, Captions [Line Items]
Capital distribution from subsidiaries				$ 12,100,000	$ 5,200,000
Proceeds from dividends received				121,000,000	$ 114,431,433	$ 135,000,000
Repayments of debt		$ 320,000,000
Swap [Member] \| FFL [Member]
Condensed Financial Statements, Captions [Line Items]
Term of swap agreement			1 year		1 year
Derivative, notional amount						100,000,000
Swap [Member] \| FFL [Member] \| LIBOR [Member]
Condensed Financial Statements, Captions [Line Items]
Basis spread on variable rate			1.28%				1.05%	1.20%
Unsecured Notes One [Member] \| Unsecured Debt [Member]
Condensed Financial Statements, Captions [Line Items]
Unsecured debt				$ 375,000,000
Interest rate, stated percentage		4.40%		4.40%
Debt issuance costs		$ 3,400,000
Discount percent		99.847%
Interest rate, effective percentage		4.45%
Unsecured Notes Two [Member] \| Revolving Credit Facility [Member]
Condensed Financial Statements, Captions [Line Items]
Loan maximum borrowing capacity	$ 50,000,000
Unsecured Notes Two [Member] \| Unsecured Debt [Member]
Condensed Financial Statements, Captions [Line Items]
Unsecured debt				$ 0
Minimum [Member] \| Revolving Credit Facility [Member]
Condensed Financial Statements, Captions [Line Items]
Debt to total capital ratio	0.15
Commitment fee on undrawn portion of facility	0.125%
Minimum [Member] \| LIBOR [Member] \| Revolving Credit Facility [Member]
Condensed Financial Statements, Captions [Line Items]
Basis spread on variable rate	1.125%
Debt to total capital ratio	0.15
Minimum [Member] \| Unsecured Notes Two [Member] \| Revolving Credit Facility [Member]
Condensed Financial Statements, Captions [Line Items]
Debt to total capital ratio	0.15
Commitment fee on undrawn portion of facility	0.125%			0.15%
Minimum [Member] \| Unsecured Notes Two [Member] \| LIBOR [Member] \| Revolving Credit Facility [Member]
Condensed Financial Statements, Captions [Line Items]
Basis spread on variable rate	1.125%
Debt to total capital ratio	0.15
Minimum [Member] \| Unsecured Notes Two [Member] \| Unsecured Debt [Member] \| LIBOR [Member]
Condensed Financial Statements, Captions [Line Items]
Basis spread on variable rate				1.125%
Maximum [Member] \| Revolving Credit Facility [Member]
Condensed Financial Statements, Captions [Line Items]
Debt to total capital ratio	0.25
Commitment fee on undrawn portion of facility	0.225%
Maximum [Member] \| LIBOR [Member] \| Revolving Credit Facility [Member]
Condensed Financial Statements, Captions [Line Items]
Basis spread on variable rate	1.625%
Debt to total capital ratio	0.25
Maximum [Member] \| Unsecured Notes Two [Member] \| Revolving Credit Facility [Member]
Condensed Financial Statements, Captions [Line Items]
Debt to total capital ratio	0.25			0.156
Commitment fee on undrawn portion of facility	0.225%
Maximum [Member] \| Unsecured Notes Two [Member] \| LIBOR [Member] \| Revolving Credit Facility [Member]
Condensed Financial Statements, Captions [Line Items]
Basis spread on variable rate	1.625%
Debt to total capital ratio	0.25
Maximum [Member] \| Unsecured Notes Two [Member] \| Unsecured Debt [Member] \| LIBOR [Member]
Condensed Financial Statements, Captions [Line Items]
Basis spread on variable rate				1.625%
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Capital distribution from subsidiaries				$ 0	$ 30,068,567	0
Payments for contributions to subsidiaries				$ 30,000,000	$ 125,000	$ 540,619