Subsequent Event (Details) $ in Millions	Feb. 05, 2019 USD ($)
Roche [Member] \| Subsequent Event [Member]
Subsequent Event (Details) [Line Items]
Litigation Settlement, Amount Awarded from Other Party	$ 21

Amount awarded from other party in judgment or settlement of litigation.

No definition available.

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