Summary of Significant Accounting Policies - Fixed Assets (Details)	12 Months Ended
Dec. 31, 2017
Building and Building Improvements
Property, Plant and Equipment [Line Items]
Fixed asset useful life	30 years
Furniture and Fixtures
Property, Plant and Equipment [Line Items]
Fixed asset useful life	5 years
Computer Software, Intangible Asset \| Minimum
Property, Plant and Equipment [Line Items]
Fixed asset useful life	3 years
Computer Software, Intangible Asset \| Maximum
Property, Plant and Equipment [Line Items]
Fixed asset useful life	5 years

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

No definition available.

Name:	us-gaap_PropertyPlantAndEquipmentUsefulLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration