Commitments and Contingencies - Operating Leases (Details) ft² in Thousands, $ in Millions	Mar. 31, 2017 USD ($) ft²
Property Subject to or Available for Operating Lease [Line Items]
Non-cancelable obligations, operating lease \| $	$ 2.4
Lease Arrangement, Expiring July 2017 \| Indianapolis
Property Subject to or Available for Operating Lease [Line Items]
Area leased (in sq ft)	85
Lease Arrangement, March 2019 To September 2023 \| Indianapolis
Property Subject to or Available for Operating Lease [Line Items]
Area leased (in sq ft)	13

Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 55
-Paragraph 40
-Subparagraph (Note 3)
-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717

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