Long-Term Debt Schedule of maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Jun. 20, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	$ 0		$ 100,000
LongTermDebtMaturitiesAverageRateInNextTwelveMonths	0.00%		1.92%
LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	$ 0		$ 50,000
LongTermDebtMaturitiesAverageRateInYearTwo	0.00%		2.04%
LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	$ 92,500		$ 100,000
LongTermDebtMaturitiesAverageRateInYearThree	3.19%		1.96%
LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	$ 100,000		$ 50,000
LongTermDebtMaturitiesAverageRateInYearFour	3.40%		3.01%
LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	$ 0		$ 100,000
LongTermDebtMaturitiesAverageRateInYearFive	0.00%		3.40%
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	$ 192,500		$ 400,000
Long-term Debt, Excluding Unamortized Cost of Debt Extinguishment Costs, Average Rate	3.30%		2.45%
Federal Home Loan Bank Advances [Member]
Debt Instrument [Line Items]
LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	$ 0		$ 100,000
LongTermDebtMaturitiesAverageRateInNextTwelveMonths	0.00%		1.92%
LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	$ 0		$ 50,000
LongTermDebtMaturitiesAverageRateInYearTwo	0.00%		2.04%
LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	$ 50,000		$ 100,000
LongTermDebtMaturitiesAverageRateInYearThree	3.01%		1.96%
LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	$ 100,000		$ 50,000
LongTermDebtMaturitiesAverageRateInYearFour	3.40%		3.01%
LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	$ 0		$ 100,000
LongTermDebtMaturitiesAverageRateInYearFive	0.00%		3.40%
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	$ 150,000		$ 400,000
Long-term Debt, Excluding Unamortized Cost of Debt Extinguishment Costs, Average Rate	3.27%		2.45%
Notes Payable to Banks
Debt Instrument [Line Items]
LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	$ 42,500
LongTermDebtMaturitiesAverageRateInYearThree	3.40%
LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour			$ 0
LongTermDebtMaturitiesAverageRateInYearFour			0.00%
Long-term Debt, Excluding Unamortized Cost of Debt Extinguishment Costs	$ 42,500	$ 50,000	$ 0
Long-term Debt, Excluding Unamortized Cost of Debt Extinguishment Costs, Average Rate	3.40%		0.00%

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 Three

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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 requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
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-Section S99
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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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