Share-Based Compensation and Employee Benefit Plans - Summary of Share-based Compensation Expense by Type of Award (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total share-based compensation	$ 6,062	$ 5,670	$ 4,775
Tax effect on share-based compensation	1,362	2,052	1,743
Net effect on net income	$ 4,700	$ 3,618	$ 3,032
Basic	$ (0.15)	$ (0.11)	$ (0.10)
Diluted	$ (0.15)	$ (0.11)	$ (0.10)
Restricted Stock Units, Including All Performance and Market Based Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total share-based compensation	$ 6,062	$ 5,433	$ 4,457
Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total share-based compensation		$ 237	$ 318

Effect on earnings per share basic.

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- Definition

Effect on earnings per share diluted.

+ References

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

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- Definition

The amount of expense, net of income tax, 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

No definition available.

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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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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