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Share Based Compensation Share Based Compensation (Narrative) (Details) - USD ($)	3 Months Ended			6 Months Ended		12 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Issued During Period, Shares, Restricted Stock Award, Gross	10,995	1,846				2,892
Number of LTIP shares authorized	20,000,000			20,000,000		20,000,000
Share-based Payment Arrangement, Expense				$ 323,000	$ 281,000
Share-based Payment Arrangement, Expense, Tax Benefit				$ 78,000	$ 67,000
5 Year Vesting Stock Appreciation Rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of awards granted			109,819
Vesting period			5 years
Percentage vested per year			20.00%
Expiration period			10 years
7 Year Vesting Stock Appreciation Rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of awards granted			28,306
Vesting period			7 years
Percentage vested per year			14.29%
Expiration period			10 years
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years	2 years				3 years
Minimum [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				3 years
Maximum [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				5 years