Defined Contribution, Maximum Annual Contribution Per Employee, Additional Contribution Per Employee Over Certain Age

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- Definition

The performance period over which over which the equity-based payment award is measured, 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

Number of annual installments for share-based compensation awards paid upon separation of service.

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ 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
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

Percentage employer matches of the employee's percentage contribution matched.

+ References

No definition available.

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- Definition

Maximum amount the employee may contribute to a defined contribution plan.

+ References

No definition available.

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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

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

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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
-Subparagraph (c)(2)(iii)(1)
-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.

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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

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- Definition

Percentage of vesting of share-based compensation awards.

+ References

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- Definition

Value, before forfeitures, of stock or other type of equity granted of any equity-based compensation plan other than an employee stock ownership plan (ESOP).

+ References

No definition available.

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Equity Compensation, Employment Agreements and other Benefit Plans - Narrative (Detail) shares in Thousands	3 Months Ended				6 Months Ended		12 Months Ended
	Jun. 30, 2018 USD ($) shares	Mar. 31, 2018 USD ($) shares	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($) installment shares	Jun. 30, 2018 USD ($) shares	Jun. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common dividends declared	$ 2,000,000		$ 1,000,000		$ 3,000,000	$ 2,000,000
401(k) Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum annual contributions per employee, amount					18,500
Maximum annual contribution per employee, additional contribution per employee over certain age					6,000
Expense related to qualified plan	$ 137,000		$ 103,000		$ 251,000	$ 215,000
Maximum \| 401(k) Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employer matching contribution, percent of match					100.00%
Employer matching contribution, percent of employees' gross pay					6.00%
Stock Award Deferral Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of installments \| installment				5
Restricted Stock \| 2007 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period					3 years
Shares available for future grants (shares) \| shares	6,000				6,000
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period					3 years
Forfeitures (shares) \| shares		241		112
Grant date fair value		$ 4,000,000		$ 2,000,000
Restricted Stock Units (RSUs) \| One year from grant date
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage					33.33%
Restricted Stock Units (RSUs) \| Two years from grant date
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage					33.33%
Restricted Stock Units (RSUs) \| Three years from grant date
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage					33.33%
Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period					3 years
Grant date fair value					$ 2,000,000		$ 3,000,000
Granted shares (shares) \| shares		133		144	133
Performance period					3 years
Performance Share Units \| One year from grant date
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage					33.33%
Performance Share Units \| Two years from grant date
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage					33.33%
Performance Share Units \| Three years from grant date
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage					33.33%
Performance Share Units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage					0.00%
Performance Share Units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage					150.00%