Long-Term Debt Schedule of maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Jun. 20, 2019
Debt Instrument [Line Items]
LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	$ 0	$ 0
LongTermDebtMaturitiesAverageRateInNextTwelveMonths	0.00%	0.00%
LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	$ 32,500	$ 0
LongTermDebtMaturitiesAverageRateInYearTwo	1.84%	0.00%
LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	$ 0	$ 92,500
LongTermDebtMaturitiesAverageRateInYearThree	0.00%	3.19%
LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	$ 0	$ 100,000
LongTermDebtMaturitiesAverageRateInYearFour	0.00%	3.40%
LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	$ 0	$ 0
LongTermDebtMaturitiesAverageRateInYearFive	0.00%	0.00%
LongTermDebtMaturitiesRepaymentsOfPrincipalInYearSix		$ 0
LongTermDebtMaturitiesAverageRateInYearSix		0.00%
Long-term Debt, Maturities, Repayments of Principal after Year Five	$ 0
Long Term Debt Maturities Average Rate In After Year Five	0.00%
Long Term Debt Maturities Repayments Of Principal After Year Six		$ 0
Thereafter		0.00%
Long-term Debt, Excluding Unamortized Cost of Debt Extinguishment Costs	$ 32,500	$ 192,500
Long-term Debt, Excluding Unamortized Cost of Debt Extinguishment Costs, Average Rate	1.84%	3.30%
Federal Home Loan Bank Advances [Member]
Debt Instrument [Line Items]
LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	$ 0	$ 0
LongTermDebtMaturitiesAverageRateInNextTwelveMonths	0.00%	0.00%
LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	$ 0	$ 0
LongTermDebtMaturitiesAverageRateInYearTwo	0.00%	0.00%
LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	$ 0	$ 50,000
LongTermDebtMaturitiesAverageRateInYearThree	0.00%	3.01%
LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	$ 0	$ 100,000
LongTermDebtMaturitiesAverageRateInYearFour	0.00%	3.40%
LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	$ 0	$ 0
LongTermDebtMaturitiesAverageRateInYearFive	0.00%	0.00%
LongTermDebtMaturitiesRepaymentsOfPrincipalInYearSix		$ 0
LongTermDebtMaturitiesAverageRateInYearSix		0.00%
Long-term Debt, Maturities, Repayments of Principal after Year Five	$ 0
Long Term Debt Maturities Average Rate In After Year Five	0.00%
Long Term Debt Maturities Repayments Of Principal After Year Six		$ 0
Thereafter		0.00%
Long-term Debt, Excluding Unamortized Cost of Debt Extinguishment Costs	$ 0	$ 150,000
Long-term Debt, Excluding Unamortized Cost of Debt Extinguishment Costs, Average Rate	0.00%	3.27%
Notes Payable to Banks
Debt Instrument [Line Items]
Long-term Debt, Excluding Unamortized Cost of Debt Extinguishment Costs	$ 32,500	$ 42,500	$ 50,000
Long-term Debt, Excluding Unamortized Cost of Debt Extinguishment Costs, Average Rate	1.84%	3.40%

Long-term Debt, Excluding Unamortized Cost of Debt Extinguishment Costs

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Long-term Debt, Excluding Unamortized Cost of Debt Extinguishment Costs, Average Rate

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Long Term Debt Maturities Average Rate In After Year Five

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Long Term Debt Maturities Average Rate In Next Twelve Months

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Long Term Debt Maturities Average Rate In Year Four

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Long Term Debt Maturities Average Rate In Year Six

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Long Term Debt Maturities Average Rate In Year Three

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Long Term Debt Maturities Average Rate In Year Two

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Long Term Debt Maturities Repayments Of Principal In Year Six

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04.(a))
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-Publisher FASB
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-Topic 470
-SubTopic 10
-Section 50
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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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