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

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Amount of cost capitalized for award under share-based payment arrangement.

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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 weighted average fair value at grant date for nonvested equity-based awards issued 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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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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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Stock-Based Plans (Summary of Restricted Stock Activity) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Weighted-average Grant Date Fair Value
Stock based compensation expense			$ 4,000	$ 9,902
Restricted Stock
Restricted Stock
Restricted stock outstanding at the beginning of the period (in shares)			406,802
Granted (in shares)			97,775
Vested (in shares)			(22,039)
Forfeited (in shares)			(54,366)
Restricted stock outstanding at the end of the period (in shares)	428,172		428,172
Weighted-average Grant Date Fair Value
Restricted stock outstanding at the beginning of the period (in dollars per share)			$ 76.27
Granted (in dollars per share)			74.93
Vested (in dollars per share)			107.75
Forfeited (in dollars per share)			96.90
Restricted stock outstanding at the end of the period (in dollars per share)	$ 71.61		$ 71.61
Stock based compensation expense	$ 2,200	$ 3,000	$ 5,900	7,700
Share based compensation costs capitalized	$ 200	$ 300	$ 900	$ 900