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Share-Based Compensation - Performance Restricted Stock Units Narrative (Details) - PRSUs shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) metric shares	Dec. 31, 2020 USD ($) metric shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 shares
Share-based compensation
Number of metrics | metric		4
Number of restricted stocks units granted (in shares)	189	292	190
Net reduction in number of awards with performance against target (in shares)	56	99	106
Increase in number of awards against target performance (in shares)			1
Reduction in number of awards with performance below target (in shares)			103
Unvested restricted stock units outstanding (in shares)	388	333	260	277
Fiscal 2019 Grants
Share-based compensation
Unvested restricted stock units outstanding (in shares)			29
Accrued Expenses and Other Current Liabilities
Share-based compensation
Aggregate liability related to performance shares outstanding (less than) | $			$ 100
Executive and senior officers
Share-based compensation
Performance payout period	1 year
Number of metrics | metric	3
Requisite service period	5 years
Recognized share-based compensation expense | $	$ 1,400	$ 1,200	1,300
Unrecognized compensation cost, net of estimated forfeitures, related to restricted stock unit awards | $	$ 2,000
Weighted-average period over which unrecognized compensation cost is expected to be recognized	2 years 2 months 12 days
Income tax benefit recognized on share-based compensation | $	$ 1,400	$ 600	$ 2,100
Executive Officer
Share-based compensation
Performance payout period	1 year
Average share price trading period	20 days	20 days
Share price, last day in trading period	20 days	20 days
Dividend yield	0.00%

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

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