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.

+ Details

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ 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 (i)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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- Definition

Amount of cost (reversal of cost) for other postretirement benefits. Excludes pension benefits.

+ References

No definition available.

+ Details

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ 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 (a)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

+ Details

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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

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)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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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.

+ Details

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

+ Details

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- Definition

Number of share instruments newly issued under a share-based compensation plan.

+ References

+ Details

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- Details

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Employee benefit plans - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award
Shares or units awarded			2,548,000	2,362,000
Unrecognized compensation expense	$ 103	$ 53	$ 103	$ 53
Employee Benefit Plans
Share-based Compensation Arrangement by Share-based Payment Award
Salaries and employee benefits expense	330	311	1,073	982
2008 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Salaries and employee benefits expense	$ 31	41	$ 93	89
2017 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Salaries and employee benefits expense		$ 52		$ 95
Common stock available for grant as awards	86,994		86,994
Non-Performance-based restricted stock \| 2008 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Shares or units awarded					2,020
Number of nonvested restricted stock awards					14,382
Shares or units vesting period					3 years
Non-Performance-based restricted stock \| 2017 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Shares or units awarded			2,548		342
Number of nonvested restricted stock awards	2,890		2,890
Performance-based restricted stock units \| 2008 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Number of nonvested restricted stock awards					7,071
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 \| 2017 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Shares or units awarded			8,920		1,196
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award
Weighted average vesting period			2 years
Restricted Stock \| 2008 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Shares or units vesting period					5 years
Unrecognized compensation expense	$ 609		$ 609