Commitments and Contingencies - Summary of Northrop Agreement Activity (Details) - Northrop [Member] $ in Millions	Mar. 31, 2016 USD ($)
Contingencies And Commitments [Line Items]
Total reimbursable costs under the Northrop Agreement	$ 189.7
Amount reimbursed to the Company through March 31, 2016	(114.7)
Potential future cost reimbursements available	75.0
Less: Receivable from Northrop included in the unaudited condensed consolidated balance sheet as of March 31, 2016	(68.7)
Potential future recoverable amounts available under the Northrop Agreement	6.3
Maximum [Member]
Contingencies And Commitments [Line Items]
Total reimbursable costs under the Northrop Agreement	$ 189.7