Increase (Decrease) in Allocated Share-based Compensation Expense Due to Change in Vesting

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- Definition

Share based compensation arrangement by share based payment award based on threshold performance achievement percentage.

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- Definition

Share based compensation arrangement by share based payment award maximum number of shares available.

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- Definition

Share based compensation arrangement by share based payment award percentage of shares issuable based on threshold performance.

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- Definition

Share based compensation arrangement by share based payment award terms of award.

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Share based compensation arrangement by share-based payment award percentage of shares issuable based on maximum performance.

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- Definition

Share based compensation arrangement by share-based payment award, percentage of shares Issuable based on target performance.

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- Definition

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

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- Definition

Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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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.

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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- Definition

The aggregate cash inflow comprised of the amount received from (a) employees to acquire the entity's shares under incentive awards, including stock option exercises and restricted stock arrangements, and (b) the excess tax benefit arising from such transactions.

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- Definition

Amount of cash inflow from exercise of option under share-based payment arrangement.

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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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- 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).

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award.

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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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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

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

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Number of options vested.

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Share-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares authorized to issued as options (in shares)		3,600,000
Share-based compensation expense		$ (2,822)	$ (2,416)	$ (5,496)
Tax benefit for share-based compensation cost		$ 100	700	$ 1,600
Unrecognized compensation costs related to unvested awards			$ 2,700
Unrecognized compensation costs, period for recognition		2 years 1 month 6 days
Term life of options		10 years
Stock awards granted vesting period			3 years	3 years
Number of options granted	210,400	210,000	57,800	125,700
Weighted average grant date fair value of the options granted	$ 2.77		$ 10.60	$ 11.84
Cash proceeds from the exercise of options		$ 100	$ 300	$ 3,100
Tax benefit recognized from stock option exercises		100	100	200
Total intrinsic value of options exercised		$ 7	$ 500	3,800
Selling, General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense				$ (1,000)
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards granted vesting period		3 years
Stock units issued (in shares)		339,498	86,516	85,393
Fair value assumptions, exercise price (in dollars per share)		$ 7.74	$ 24.55	$ 24.29
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value		$ 2,900	$ 1,800	$ 2,100
TSR Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock units issued (in shares)	136,000
Percentage of shares issuable based on threshold performance		50.00%
Percentage of shares issuable based on target performance		100.00%
Percentage of shares issuable based on maximum performance		150.00%
Threshold performance, percentage		35.00%	35.00%	35.00%
ROIC Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense			$ 800
Decrease in share-based compensation expense from change in vesting		$ 1,100	$ 1,200
Stock units issued (in shares)	174,000
Percentage of shares issuable based on threshold performance		35.00%
Percentage of shares issuable based on target performance		100.00%
Percentage of shares issuable based on maximum performance		150.00%
Threshold performance, percentage		4.70%	15.50%	15.00%
Options awards vested		0
Officers and Key Employees \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards granted vesting period		3 years
Non-executive Directors \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards granted vesting period		1 year	1 year	1 year
Restatement Adjustment \| ROIC Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividends accrued for performance share units		$ (100)