Stock-Based Compensation Plans - Options (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
Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)	0	205,000	0	386,115
Weighted-average grant-date fair value (in dollars per share)	$ 0	$ 11.45	$ 0	$ 7.48
Compensation expense	$ 1,295	$ 1,995	$ 4,823	$ 22,398
RSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 1,684	$ 0	$ 3,674	$ 0
RSUs granted (in shares)	0	0	493,878	0
Weighted-average grant-date fair value (in dollars per share)	$ 0	$ 0	$ 38.91	$ 0

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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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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Gross number of share options (or share units) granted during the period.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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