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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Number of shares authorized for issuance under share-based payment arrangement.

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Stock-Based Compensation - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award
Stock-compensation expense	$ 3,158	$ 2,785	$ 9,336	$ 8,277
Unrecognized compensation cost	$ 18,920		$ 18,920
Future period share-based compensation expense period of recognition (in years)			1 year 4 months 24 days
Common stock
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares authorized					2,500,000
Number of shares available for grant	1,900,000		1,900,000