The increase (decrease) during the period in the number of shares authorized.

No definition available.

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Balance Type:	na
Period Type:	duration

- Definition

Percentage weight of each metric (core return on tangible common equity and relative total shareholder return) that is used to calculate the total performance share award opportunity.

+ References

No definition available.

+ Details

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- Definition

Percentage of the number of performance shares granted that represents can earn based on achieving certain performance metrics.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

This element represents the amount of time performance shares may be earned based on achieving certain performance metrics.

+ 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

+ Details

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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

+ Details

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Balance Type:	na
Period Type:	duration

- 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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Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

- Definition

Percentage of vesting of share-based compensation awards.

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of share options (or share units) exercised during the current 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)(2)
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Name Accounting Standards Codification
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

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Period Type:	duration

- Details

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- Details

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- Details

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- Details

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Share-Based Compensation - Narrative (Details) - shares		1 Months Ended	12 Months Ended
Share-Based Compensation - Narrative (Details) - shares	May 17, 2017	May 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, increase shares authorized (in shares)	100,000,000
Stock options exercised in period (in shares)			42,000
2018 Stock and Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, increase shares authorized (in shares)		2,000,000
Directors Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)			14,000	16,000
Nonqualified Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted in period (in shares)			0	0	0
Stock options exercised in period (in shares)			0	0	0
Restricted Stock And Restricted Stock Unit Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			3 years
Granted (in shares)			427,000
Restricted Stock And Restricted Stock Unit Awards \| Vesting After Two Years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights percentage			50.00%
Restricted Stock And Restricted Stock Unit Awards \| Vesting After Three Years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights percentage			50.00%
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of internal and external performance metric analysis			3 years
Metric weighting (percent)			50.00%
Granted (in shares)			133,000
Performance Shares \| Vesting After Three Years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights percentage			33.33%
Performance Shares \| Vesting After Fourth Years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights percentage			33.33%
Performance Shares \| Vesting After Fifth Year
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights percentage			33.33%
Performance Shares \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of shares earned of those granted based on performance			0.00%
Performance Shares \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of shares earned of those granted based on performance			200.00%