Gross number of share options (or share units) assumed from merger during the period.

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Weighted average per share amount assumed from merger.

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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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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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Number of shares authorized for issuance under share-based payment arrangement.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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

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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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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested 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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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Percentage of vesting of award under share-based payment arrangement.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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Share-Based Compensation - Stock Options (Details) - USD ($) $ / shares in Units, $ in Thousands		2 Months Ended	3 Months Ended			9 Months Ended		84 Months Ended
	Jan. 31, 2012	Mar. 31, 2012	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2020	Dec. 31, 2012	Dec. 31, 2019
Aggregate Intrinsic Value
Outstanding at the end of the period			$ 1,529			$ 1,529
Exercisable at the end of the period			$ 1,529			$ 1,529
Stock Options
Number of shares
Outstanding at the beginning of the period (in shares)					176,888	176,888
Assumed stock options and warrants from CSFL merger (in shares)						136,831
Exercised (in shares)						(23,012)
Outstanding at the end of the period (in shares)			290,707			290,707		176,888
Exercisable at the end of the period (in shares)			290,707			290,707
Weighted-Average Exercise Price
Outstanding at the beginning of the period (in dollars per share)					$ 67.14	$ 67.14
Assumed stock options and warrants from CSFL merger (in dollars per share)						37.85
Exercised (in dollars per share)						32.14
Outstanding at the end of the period (in dollars per share)			$ 56.13			56.13		$ 67.14
Exercisable at the end of the period (in dollars per share)			$ 56.13			56.13
Weighted-average fair value of options granted during the year (in dollars per share)						$ 0.00
Weighted-Average Remaining Contractual Life
Outstanding at the end of the period						4 years 6 months 25 days
Exercisable at the end of the period						4 months 17 days
Restricted Stock
Number of shares
Assumed stock options and warrants from CSFL merger (in shares)						9,755
Weighted-Average Exercise Price
Assumed stock options and warrants from CSFL merger (in dollars per share)						$ 60.27
Restricted Stock \| Maximum
Share-Based Compensation
Vesting period						12 months
Restricted Stock \| Minimum \| Employees
Share-Based Compensation
Vesting period						4 years
2012 plan
Share-Based Compensation
Options granted (in shares)						0
2019 plan
Share-Based Compensation
Number of shares registered			1,000,000			1,000,000
2004 plan
Number of shares
Granted (in shares)	0	0	0	0	0		0	0
Plan 2004 And 2012 \| Incentive stock options
Share-Based Compensation
Vesting percentage						25.00%
Expiration period						10 years
Plan 2004 And 2012 \| Incentive stock options \| Maximum
Share-Based Compensation
Vesting period						4 years