Commitments and Contingencies - Restructuring (Details) $ in Millions		9 Months Ended
Mar. 27, 2018 office	Sep. 30, 2018 USD ($)
Restructuring Cost and Reserve [Line Items]
Number of offices consolidated \| office	2
Employee Termination \| New Jersey Program
Restructuring Cost and Reserve [Line Items]
Employee termination costs		$ 1.5
Employee Termination \| Sales Territory Program
Restructuring Cost and Reserve [Line Items]
Employee termination costs		$ 0.5

Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

Name:	us-gaap_RestructuringCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration