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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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Stock Based Compensation (Details) - USD ($)	1 Months Ended	3 Months Ended					6 Months Ended		12 Months Ended
Stock Based Compensation (Details) - USD ($)	Aug. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2019	Jun. 30, 2019	Sep. 30, 2018	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019	Dec. 31, 2017
Restricted stock and RSU grants:
Weighted average per share value of non-vested shares (based on grant price) (in dollars per share)			$ 25.65		$ 24.60		$ 25.65	$ 24.60
Value of stock vested during the year (based on grant price)			$ 585,000				$ 3,589,000	$ 2,304,000
Weighted average per share value of shares forfeited during the year (based on grant price) (in dollars per share)			$ 24.03				$ 24.03
Restricted stock and RSU grants
Total charge to operations:
Total charge to operations			$ 1,329,000		$ 938,000		$ 2,305,000	$ 1,892,000
Restricted stock
Stock Based Compensation
Vesting period							5 years
Number of shares vested							122,125	112,150
Summary of the activity of the incentive plans
Average per share grant price (in dollars per share)							$ 28.10	$ 25.70
Deferred compensation to be recognized over vesting period			$ 4,202,000		$ 3,856,000		$ 4,202,000	$ 3,856,000
Number of non-vested shares:
Non-vested beginning of period (in shares)		701,675	701,675	689,150	689,150		674,250	651,250	651,250
Number of shares awarded							149,550	150,050
Non-vested end of period (in shares)			701,675		689,150		701,675	689,150	674,250
Vested during year (in shares)							(122,125)	(112,150)
Total charge to operations:
Total charge to operations			$ 884,000		$ 843,000		$ 1,759,000	$ 1,686,000
Total compensation costs related to non-vested awards that have not yet been recognized			$ 9,583,000				$ 9,583,000
Weighted average remaining vesting period							2 years 7 months 6 days
RSUs
Stock Based Compensation
Number of shares forfeited			51,907				51,907		5,250
Number of shares vested			24,343				24,343
Number of non-vested shares:
Non-vested beginning of period (in shares)		148,776	225,026	152,500	152,500		225,026	152,500	152,500
Number of shares awarded		75,026		77,776		76,250
Forfeitures (in shares)			(51,907)				(51,907)		(5,250)
Non-vested end of period (in shares)			148,776		152,500		148,776	152,500	225,026
Vested during year (in shares)			(24,343)				(24,343)
Total charge to operations:
Total charge to operations			$ 445,000		$ 95,000		$ 546,000	$ 206,000
Total compensation costs related to non-vested awards that have not yet been recognized			$ 963,000				$ 963,000
Weighted average remaining vesting period							1 year 6 months
RSUs \| Awards granted in 2018 and 2019
Stock Based Compensation
Number of shares forfeited							0
Number of shares vested							0
Number of non-vested shares:
Forfeitures (in shares)							0
Vested during year (in shares)							0
TSR Awards
Stock Based Compensation
Percentage of RSUs to vest upon achievement of specified criteria							50.00%
ROC Awards
Stock Based Compensation
Percentage of RSUs to vest upon achievement of specified criteria							50.00%
2019 Incentive Plan
Stock Based Compensation
Maximum number of shares authorized for issuance			750,000				750,000
Number of non-vested shares:
Number of shares awarded							224,576
2019 Incentive Plan \| Restricted stock
Number of non-vested shares:
Number of shares awarded							149,550
2019 Incentive Plan \| RSUs
Number of non-vested shares:
Number of shares awarded							75,026
2016 and 2012 Incentive Plans
Number of non-vested shares:
Non-vested beginning of period (in shares)		625,875
Non-vested end of period (in shares)			625,875				625,875
2016 and 2012 Incentive Plans \| Restricted stock
Number of non-vested shares:
Non-vested beginning of period (in shares)		552,125
Non-vested end of period (in shares)			552,125				552,125
2016 and 2012 Incentive Plans \| RSUs
Stock Based Compensation
Number of shares forfeited	51,907
Number of shares vested	24,343
Number of non-vested shares:
Non-vested beginning of period (in shares)		73,750
Number of shares awarded										76,250
Forfeitures (in shares)	(51,907)
Non-vested end of period (in shares)			73,750				73,750
Vested during year (in shares)	(24,343)
Pay-for-performance program \| RSUs \| Awards granted in 2018
Stock Based Compensation
Aggregate fair value of the shares granted			$ 918,000				$ 918,000
Pay-for-performance program \| RSUs \| Awards granted in 2019
Stock Based Compensation
Aggregate fair value of the shares granted			$ 986,000				$ 986,000