Employee Benefit Plan	12 Months Ended
Dec. 31, 2018
Postemployment Benefits [Abstract]
Employee Benefit Plan	12. Employee Benefit Plan. In 2007, the Company adopted a 401(K) plan for its employees whereby eligible employees may contribute up to the maximum amount permitted by the Internal Revenue Code of 1986, as amended. In June 2016, the Company adopted a policy to match a portion of employee contributions for all qualified employees participating in the 401(k) plan. For the years ended December 31, 2018, 2017 and 2016, the Company recorded expenses of $2.5 million, $2.2 million and $1.3 million for matching contributions, 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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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
-Topic 712
-URI http://asc.fasb.org/topic&trid=2197446

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 710
-URI http://asc.fasb.org/topic&trid=2127225

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

Name:	us-gaap_CompensationAndEmployeeBenefitPlansTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration