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Share-Based Compensation Arrangement By Share-Based Payment Award, Shares Authorized, Percentage Of Common Stock Outstanding

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Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Percentage

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instrument Other Than Option, Cumulative Grant Date Fair Value

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Exchange of Options

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

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Aggregate number of common shares reserved for future issuance.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Amount of cost to be recognized for option under share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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STOCK-BASED AWARDS - Additional Information (Details) - USD ($)	1 Months Ended		3 Months Ended			9 Months Ended
	Dec. 31, 2017	Jul. 31, 2017	Sep. 30, 2020	Sep. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019	Jun. 10, 2020	Dec. 31, 2019
Weighted Average Grant Date Fair Value
Common stock, shares authorized			100,000,000			100,000,000			100,000,000
Common stock, shares issued			46,317,000			46,317,000			42,790,000
Stock-based compensation expense			$ 2,623,000	$ 4,467,000		$ 8,356,000	$ 13,623,000
Restricted Stock Awards
Units
Outstanding-beginning of year (in shares)						1,051,000
Granted at fair value (in shares)						478,000
Vested (in shares)						(696,000)
Forfeited (in shares)						(156,000)
Outstanding-end of period (in shares)			677,000			677,000
Weighted Average Grant Date Fair Value
Outstanding-beginning of year (in dollars per share)						$ 26.22
Granted at fair value (in dollars per share)						9.82
Vested (in dollars per share)						23.50
Forfeited (in dollars per share)						24.72
Outstanding-end of period (in dollars per share)			$ 17.78			$ 17.78
Restricted Stock Awards \| First year
Stock-Based Awards
Annual award vesting percentage						33.30%
Restricted Stock Awards \| Second year
Stock-Based Awards
Annual award vesting percentage						33.30%
Restricted Stock Awards \| Third year
Stock-Based Awards
Annual award vesting percentage						33.30%
Medici Ventures
Weighted Average Grant Date Fair Value
Common stock, shares authorized		1,500,000
Common stock, shares issued			900,000			900,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares			470,000			470,000
Medici Ventures \| Employee Stock Options
Units
Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount			$ 282,000			$ 282,000
Weighted Average Grant Date Fair Value
Restricted stock units authorized, percentage		9.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross						13,650
tZero.com, Inc. \| Restricted Stock Awards
Units
Granted at fair value (in shares)						11,528,016
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount								$ 6,900,000
Weighted Average Grant Date Fair Value
Restricted stock units authorized, percentage	5.00%
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Exchange of Options						7,851,016
Restricted Stock Unit Awards not Included in Stock Option Exchange						3,677,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount			3,500,000			$ 3,500,000
tZero.com, Inc. \| Employee Stock Options
Units
Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount			$ 46,000			$ 46,000
Weighted Average Grant Date Fair Value
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross						60,000
Equity Incentive Plan, One-Year Vesting \| Restricted Stock Awards
Stock-Based Awards
Vesting period					1 year
Units
Granted at fair value (in shares)					502,765
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instrument Other Than Option, Cumulative Grant Date Fair Value					$ 8,600,000
2017 Stock Option Plan \| Medici Ventures \| Employee Stock Options
Weighted Average Grant Date Fair Value
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number			130,000			130,000