Employee Benefit Plans	12 Months Ended
Dec. 31, 2018
Compensation And Retirement Disclosure [Abstract]
Employee Benefit Plans	14. EMPLOYEE BENEFIT PLANS The Company covers substantially all U.S. salaried employees with a defined contribution 401(k) plan. Each salaried employee of the Company who has attained the age of 21 is eligible to participate in the 401(k) plan on their first day of employment. Any employer contributions to the 401(k) plan are entirely at the discretion of the Company. The Company accrued expenses relating to employer matching contributions to the 401(k) plan for the years ended December 31, 2018, 2017 and 2016, in the amounts of $2,379, $2,264 and $1,971, respectively.

The entire disclosure for an entity's employee compensation and benefit plans, including, but not limited to, postemployment and postretirement benefit plans, defined benefit pension plans, defined contribution plans, non-qualified and supplemental benefit plans, deferred compensation, share-based compensation, life insurance, severance, health care, unemployment and other benefit plans.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-URI http://asc.fasb.org/topic&trid=2228938

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 710
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-URI http://asc.fasb.org/topic&trid=2235017

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