Related Party Transactions (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Jun. 30, 2018	Jun. 30, 2017
RSL and RSI \| RSL and RSI \| Service Agreement
Related Party Transaction [Line Items]
Expenses incurred under services agreements	$ 3.2	$ 1.1
RSL \| RSL \| Share-based Compensation, Expense Allocated to Company
Related Party Transaction [Line Items]
Expenses incurred under services agreements	$ 0.2	$ 0.2

Costs of sales and operating expenses for the period incurred from transactions with related parties.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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