v3.19.2

Revenue from Contract with Customers (Narrative) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2019 | Jun. 30, 2019
Revenue from Contract with Customer [Abstract] |  |
Deferred Revenue, Revenue Recognized | $ 13.8 | $ 84.0

X
- Definition Amount of revenue recognized that was previously reported as deferred or unearned revenue. + References No definition available. + Details
Name: | us-gaap_DeferredRevenueRevenueRecognized1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_RevenueFromContractWithCustomerAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration