Nature of Operations - Narrative (Details) $ in Millions	12 Months Ended
Dec. 31, 2017 USD ($) region sales_agent
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Reduction of full-time equivalent headcount, percent	51.00%
Decrease in operating expense	$ (8.4)
Restructuring costs and asset impairment charges	$ 1.8
Number of geographic regions \| region	6
Number of sales agents \| sales_agent	30

Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan and expenses resulting from the write-down of assets. Excludes expenses related to a business combination, a discontinued operation or an asset retirement obligation.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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