Share-based Compensation Arrangement by Share-based Payment Award, Award Required Holding Period

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Share-based Compensation Arrangement by Share-based Payment Award, Offering Period

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Aggregate dividends declared during the period for each share of common stock outstanding.

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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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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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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

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Number of options outstanding, including both vested and non-vested options.

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Percentage of vesting of award under share-based payment arrangement.

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

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Aggregate change in value for stock issued during the period as a result of employee stock purchase plan.

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Amount of stock repurchase plan authorized.

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Stockholders' Equity - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Feb. 26, 2020	Aug. 31, 2018	Jul. 25, 2016	May 16, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock authorized (shares)	75,000,000	75,000,000
Common stock par value (usd per share)	$ 0.0001	$ 0.0001
Preferred stock authorized (shares)	25,000,000	25,000,000
Preferred stock par value (usd per share)	$ 0.0001	$ 0.0001
Stock options outstanding (shares)	0	0
Common stock outstanding (shares)	19,071,614	19,389,066
Preferred stock outstanding (shares)	0	0
Dividends declared (usd per share)	$ 0.50	$ 0.50	$ 0.50
Common stock repurchase program, authorized amount					$ 10,000
Issuance of common stock under the Employee Stock Purchase Plan	$ 264	$ 247	$ 256
2012 Equity Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity securities granted (shares)							2,194,986
2012 Equity Plan \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	1 year
2012 Equity Plan \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
2012 Equity Plan \| Contingent restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
2011 Long Term Incentive Plan \| Restricted Stock and RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested shares outstanding (shares)	419,426	404,325
Compensation cost not yet recognized	$ 3,100
Compensation cost not yet recognized, period for recognition	1 year 7 months 6 days
2011 Long Term Incentive Plan \| Contingent restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested shares outstanding (shares)	273,788
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity securities granted (shares)						250,000
Award required holding period	2 years
Issuance of common stock under the Employee Stock Purchase Plan (shares)	23,299	20,120
Issuance of common stock under the Employee Stock Purchase Plan	$ 300	$ 200
Maximum \| ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Offering period	6 months
Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend rate (usd per share)				$ 0.125
Dividends declared				$ 2,400
Tranche one \| 2012 Equity Plan \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage	33.33%
Tranche two \| 2012 Equity Plan \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage	33.33%
Tranche three \| 2012 Equity Plan \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage	33.33%