Summary of Accounting Policies Summary of Accounting Policies - Goodwill and Other Intangible Assets (Details)	12 Months Ended
Dec. 31, 2019 reporting_unit
Accounting Policies [Abstract]
Number of reporting units	4

Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

No definition available.

Name:	us-gaap_NumberOfReportingUnits
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration