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

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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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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Stock-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant	11,557,874		11,557,874
Shares granted			2,390,345
Shares granted, weighted average grant date fair value			$ 11.64
Unrecognized compensation cost relating to unvested restricted stock	$ 78,100		$ 78,100
Unrecognized compensation cost relating to unvested restricted stock, recognition period (in years)			3 years 2 months 12 days
Four Zero One K Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employer Discretionary Contribution Amount	1,300		$ 3,000
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted			2,390,345	1,940,798
Shares granted, weighted average grant date fair value			$ 11.64	$ 10.42
Compensation and benefits expense	$ 8,100	$ 7,600	$ 16,300	$ 15,500
Restricted Stock \| Share-based Payment Arrangement, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted, vesting period			3 years	3 years
Restricted Stock \| Share-based Payment Arrangement, Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted, vesting period			5 years	5 years
Performance-Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	446,181		865,855		0
Compensation and benefits expense	$ 540,000		$ 947,000
Vesting rights, description			The PSUs have a performance period of January 1, 2019 to December 31, 2022 and vest on April 1, 2022, subject to adjustment or forfeiture, based upon the achievement by the Company of certain performance standards.