Income Taxes - Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Gross unrecognized tax benefits	$ 3,682	$ 2,106
Increase in tax position for current year	169	1,752
Increase in tax position for prior years	241	135
Decrease in tax position for prior years	(720)	(311)
Decrease for lapse of statute of limitations/ settlements	(1,418)
Gross unrecognized tax benefits	$ 1,954	$ 3,682

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Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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