Share-Based Compensation - Total Compensation Cost Recognized for Share-based Awards (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Share-based compensation expense	$ 8,295	$ 8,146	$ 8,550
Capitalized share-based compensation	946	962	1,215
Total share-based compensation	$ 9,241	$ 9,108	$ 9,765

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

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