Revenue from Contracts With Customers - Practical Expedients (Details)	3 Months Ended
Mar. 31, 2019
Practical expedients
Practical expedient - nondisclosure of transaction price for future performance obligations	true

Indicates (true false) whether practical expedient was elected not to disclose amount of transaction price allocated to remaining performance obligation and explanation of expected timing of revenue recognition for reporting period presented prior to date of initial application under retrospective method.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 65
-Paragraph 1
-Subparagraph (f)(3)
-URI http://asc.fasb.org/extlink&oid=113356391&loc=SL49131195-203048

Name:	us-gaap_RevenuePracticalExpedientInitialApplicationAndTransitionNondisclosureOfTransactionPriceAllocationToRemainingPerformanceObligation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:booleanItemType
Balance Type:	na
Period Type:	duration