Share-based Compensation Arrangement by Share-based Payment Award, Options Expiration Period After Date of Grant

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- Definition

Share-based Compensation Arrangement By Share-based Payment Award, Vesting Percentage After Change In Control

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Period Before Change In Control

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Vesting Period After Change In Control

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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.

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- Definition

Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to excess tax benefit for share-based compensation cost.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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- Definition

Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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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

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

Net number of non-option equity instruments granted to participants.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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

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

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

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No definition available.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

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No definition available.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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Stock-based Compensation (Narrative) (Details) - USD ($)			1 Months Ended	3 Months Ended		12 Months Ended
	Jan. 04, 2019	Jan. 02, 2018	May 31, 2016	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excess tax benefit related to share-based payment awards						$ 674,000	$ 1,200,000
Number of options granted (in shares)						0	0	0
Typical options expiration period after date of grant						10 years
Intrinsic value for the total of all options exercised						$ 231,000
Fair value of shares under vested stock options and awards						0
Cash received from options exercised						$ 121,000	$ 361,000
Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of stock awarded for services performed (in shares)						36,462	17,106	24,153
Period One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, award vesting periods						3 years
Period Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, award vesting periods						4 years
Period Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, award vesting periods						5 years
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, award service periods						5 years
Share-based compensation costs						$ 0	$ 0	$ 0
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation costs						$ 4,400,000	$ 3,200,000	$ 2,600,000
Equity instruments other than options, granted (in shares)				52,153	55,655
Number of shares of stock awarded for services performed (in shares)						123,711	109,373	143,721
Performance-based RSUs \| Period One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, award vesting periods					1 year	1 year
Equity instruments other than options, granted (in shares)				18,988	27,570
Performance-based RSUs \| Period Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, award vesting periods				3 years		3 years
Equity instruments other than options, granted (in shares)				16,108	9,032
Long-Term Incentive Plan 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for issuance (in shares)						437,893
Long-Term Incentive Plan 2012 \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based unrecognized compensation costs						$ 4,200,000
Long-Term Incentive Plan 2012 \| Performance-based RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, vesting percentage after change in control						100.00%
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for issuance (in shares)						444,852
Share-based compensation costs						$ 91,000	$ 153,000	$ 183,000
Maximum number of shares issuable (in shares)			500,000
Stocks purchased under the plan (in shares)		22,903						32,245
ESPP \| Fair Market Value at Investment Date
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase price of common stock, percent			95.00%
2016 RSUs \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, award vesting periods						3 years
2017 RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, period before change in control						6 months
2017 RSUs \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, award vesting periods						3 years
2017 RSUs \| Long-Term Incentive Plan 2012 \| Performance-based RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, vesting percentage after change in control						100.00%
Share-based compensation, vesting period after change in control						24 months
Subsequent Event \| ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stocks purchased under the plan (in shares)	32,331