Revenue from Contracts with Customers (Summary of Remaining Performance Obligations/Backlog) (Details) $ in Thousands	Sep. 30, 2018 USD ($)
Disaggregation Of Revenue [Line Items]
Estimated recognition of Backlog	$ 39,135
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2018-10-01
Disaggregation Of Revenue [Line Items]
Estimated recognition of Backlog	$ 35,878
Revenue, remaining performance obligation, expected timing of satisfaction, period	9 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2019-07-01
Disaggregation Of Revenue [Line Items]
Estimated recognition of Backlog	$ 2,716
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2020-07-01
Disaggregation Of Revenue [Line Items]
Estimated recognition of Backlog	$ 335
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2021-07-01
Disaggregation Of Revenue [Line Items]
Estimated recognition of Backlog	$ 195
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2022-07-01
Disaggregation Of Revenue [Line Items]
Estimated recognition of Backlog	$ 11
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year