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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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Employee Stock Benefit Plans - Workforce Reduction (Details) $ in Thousands		3 Months Ended
	Feb. 07, 2019 employee	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)
Employee Stock Benefit Plans
Share-based compensation expense		$ 6,364	$ 13,934
Reduction in Workforce, February 7, 2019
Workforce Reduction
Number of employees expected to be eliminated \| employee	35
Employee Stock Benefit Plans
Share-based compensation expense			$ 500