Commitments and Contingencies Commitments and Contingencies (Details) - USD ($) $ / shares in Units, $ in Millions	Mar. 31, 2018	Mar. 08, 2018
Other Commitments [Line Items]
Sale of Stock, Price Per Share		$ 15.25
Guarantor Obligations, Current Carrying Value	$ 0

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82913245&loc=d3e12069-110248

Name:	us-gaap_GuaranteeObligationsCurrentCarryingValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant