Percentage Of Target Award Opportunities Maximum In Certain Cases

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- Definition

Performance Based Stock Awards Vesting Period

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No definition available.

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- Definition

Performance Shares Awards As Percentage Of Target

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Percentage Of Target Award Participants Earn

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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
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901

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-Name Accounting Standards Codification
-Topic 718
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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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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.

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-Publisher FASB
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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued 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).

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

Date the equity-based award expires, in CCYY-MM-DD format.

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-Publisher FASB
-Name Accounting Standards Codification
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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.

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No definition available.

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- Definition

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

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-Publisher FASB
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-Topic 718
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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.

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- Definition

Number of shares issued under share-based payment arrangement.

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Incentive Compensation Plan - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions																											12 Months Ended
	Feb. 21, 2019	Nov. 26, 2018	May 29, 2018	Mar. 26, 2018	Feb. 28, 2018	Feb. 26, 2018	Mar. 24, 2017	Feb. 23, 2017	Dec. 19, 2016	Sep. 30, 2016	Sep. 19, 2016	Jun. 07, 2016	Mar. 01, 2016	Mar. 01, 2016	Mar. 01, 2016	Feb. 18, 2016	Dec. 30, 2015	Jun. 26, 2015	Feb. 20, 2015	Feb. 05, 2015	Jan. 26, 2015	Jan. 15, 2015	Nov. 18, 2014	Apr. 08, 2014	Mar. 25, 2014	Mar. 05, 2014	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant Price (in dollars per share)																											$ 14.22	$ 14.50	$ 12.99
Maximum number of shares that are available to be awarded																											5,000,000
Vesting period of restricted stock	0 years				0 years			0 years								0 years	0 years				0 years
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant																											2,930,128
Performance Based Stock Awards Vesting Period	3 years				3 years			3 years								3 years	5 years				3 years
Share Based Compensation Arrangement By Share Based Payment Award Percentage Of Target Award Participants Earn	40.00%				40.00%			40.00%								40.00%					40.00%
Performance Shares Awards As Percentage Of Target	100.00%				100.00%			100.00%								100.00%					100.00%
Percentage Of Target Award Opportunities Maximum In Certain Cases	200.00%				200.00%			200.00%								200.00%					200.00%
Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued (in shares)	63,000
Grant Price (in dollars per share)	$ 14.22
Vesting Date	Feb. 22, 2022
Vesting period of restricted stock	1 year
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued (in shares)	15,000	2,000	3,000	2,000		77,500			15,000	10,000	33,000	10,000	5,000	20,000	10,000			1,000	10,000			20,000	3,500	27,500	46,000	5,000
Grant Price (in dollars per share)	$ 14.22	$ 13.82	$ 15.44	$ 14.08		$ 14.49			$ 13.96	$ 10.09	$ 10.02	$ 9.34	$ 8.84	$ 8.84	$ 8.84		$ 9.18	$ 9.84	$ 8.45			$ 8.38	$ 9.26	$ 8.89	$ 9.18	$ 8.75
Vesting Date	Feb. 22, 2022	Nov. 26, 2021	May 29, 2021	Mar. 26, 2021		Feb. 26, 2021			Dec. 19, 2019	Sep. 30, 2019	Sep. 19, 2019	Jun. 07, 2019	Mar. 01, 2019	Aug. 31, 2017	Mar. 01, 2019			Jun. 26, 2018	Aug. 31, 2017			Jan. 15, 2017	Nov. 17, 2017	Apr. 08, 2017	Mar. 24, 2017	Mar. 04, 2017
Share-based Payment Arrangement, Expense																											$ 2.7	$ 2.6	$ 3.8
Unrecognized compensation cost related to unvested restricted stock																											$ 3.1
Vesting period of restricted stock	1 year	1 year	1 year	1 year		1 year	1 year		3 years	1 year	3 years	1 year	1 year	1 year	1 year			1 year	1 year			1 year	1 year	3 years	1 year	1 year
Restricted Stock [Member] \| Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued (in shares)																				50,000
Grant Price (in dollars per share)																				$ 8.55
Vesting Date																				Feb. 05, 2018
Vesting period of restricted stock																				1 year
Time [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant Price (in dollars per share)	$ 14.22				$ 14.17			$ 13.29
Component 3 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant Price (in dollars per share)	13.07				13.25
Component 2 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant Price (in dollars per share)	$ 16.62				$ 15.83			$ 15.09
March 24, 2017 Grant 2 [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued (in shares)							7,000
Grant Price (in dollars per share)							$ 12.99
Vesting Date							Aug. 31, 2017
Vesting period of restricted stock							1 year
March 24, 2017 Grant 4 [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued (in shares)							7,000
Grant Price (in dollars per share)							$ 12.99
Vesting Date							Aug. 31, 2017
March 24, 2017 Grant 3 [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued (in shares)							7,000
Grant Price (in dollars per share)							$ 12.99
Vesting Date							Mar. 24, 2020
Vesting period of restricted stock							1 year
March 24, 2017 Grant 1 [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued (in shares)							5,000
Grant Price (in dollars per share)							$ 12.99
Vesting Date							Mar. 24, 2020
Vesting period of restricted stock							1 year