Employee Benefit Plans	12 Months Ended
Dec. 31, 2018
Postemployment Benefits [Abstract]
Employee Benefit Plans	11. EMPLOYEE BENEFIT PLANS The Company has a 401(k) retirement and savings plan (the “401(k) Plan”) covering employees of Wave USA. The 401(k) Plan allows employees to make contributions up to the maximum allowable amount set by the IRS. Under the 401(k) Plan, the Company may make discretionary contributions as approved by the board of directors. The Company made contributions of $0.7 million and $0.4 million in the years ended December 31, 2018 and 2017, respectively. The Company did not make contributions to the 401(k) Plan during the year ended December 31, 2016.

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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-URI http://asc.fasb.org/topic&trid=2228938

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-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
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