The average return on equity period used for conditions for vesting of performance-based restricted stock units.

No definition available.

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- Definition

The cumulative diluted earnings per share period used for conditions for vesting of performance-based restricted stock units.

+ References

No definition available.

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- Definition

Period which an employee's prior period stock cliff vests, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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-Publisher FASB
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-SubTopic 10
-Section S99
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-Publisher FASB
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
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- Definition

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).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Paragraph 2
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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(2)
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- Definition

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.

+ References

No definition available.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Number of shares issued under share-based payment arrangement.

+ References

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Stock plans - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award
Shares or units awarded		2,548
Unrecognized compensation expense		$ 92
2008 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Shares or units awarded	673
Number of nonvested restricted stock awards	6,379
Forfeited shares	763
Share based compensation expense	$ 122	123	$ 156
2017 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Common stock available for grant as awards	72,535
Forfeited shares	306
Share based compensation expense	$ 433	$ 149	$ 21
Non-Performance-based restricted stock
Share-based Compensation Arrangement by Share-based Payment Award
Shares or units vesting period		3 years
Non-Performance-based restricted stock \| 2008 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Shares or units awarded		2,548
Vested shares	2,493
Non-Performance-based restricted stock \| 2017 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Shares or units awarded	3,855	2,140
Vested shares	114
Performance-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award
Shares or units vesting period		3 years
Cumulative diluted earnings per share period used for conditions for vesting of performance-based restricted stock units		3 years
Average return on equity period used for conditions for vesting of performance-based restricted stock units		3 years
Performance-based restricted stock units \| 2008 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Number of nonvested restricted stock awards		8,920
Performance-based restricted stock units \| 2017 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Number of nonvested restricted stock awards	13,490	928
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award
Granted shares	17,345	11,468	10,628
Vested shares	10,120	2,607	10,542
Number of nonvested restricted stock awards	27,465	21,309	12,448	12,362
Forfeited shares	1,069
Shares or units cliff vesting period		5 years
Unrecognized compensation expense	$ 486
Weighted average vesting period	1 year 9 months 18 days