XML 31 R14.htm IDEA: XBRL DOCUMENT
v3.8.0.1

401(k) Plan | 12 Months Ended
--- | ---
Dec. 31, 2017
Compensation And Retirement Disclosure [Abstract] |
401(k) Plan | 7. 401(k) Plan Effective January 1997, the Company established a deferred compensation plan (the “401(k) Plan”) pursuant to Section 401(k) of the Internal Revenue Code of 1986, as amended (the “Code”), whereby substantially all employees are eligible to contribute up to 60 percent of their pretax earnings, not to exceed amounts allowed under the Code. The Company makes discretionary contributions to the 401(k) Plan equal to 100 percent of each employee’s pretax contributions up to 5 percent of his or her eligible compensation, subject to limitations under the Code. The Company’s total contributions to the 401(k) Plan were $3.3 million, $2.1 million, and $1.0 million for the years ended December 31, 2017, 2016, and 2015, respectively.

X
- References No definition available. + Details
Name: | us-gaap_CompensationAndRetirementDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The entire disclosure for pension and other postretirement benefits. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -URI http://asc.fasb.org/topic&trid=2235017 + Details
Name: | us-gaap_PensionAndOtherPostretirementBenefitsDisclosureTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration