Commitments and Contingencies - Summary of Northrop Agreement Activity (Details) - Northrop [Member] $ in Millions	Nov. 30, 2015 USD ($)
Site Contingency [Line Items]
Total reimbursable costs under the Northrop Agreement	$ 189.7
Amount reimbursed to the Company through November 30, 2015	(113.2)
Potential future cost reimbursements available	76.5
Receivable from Northrop in excess of the annual limitation included in the consolidated balance sheet as of November 30, 2015	(68.7)
Potential future recoverable amounts available under the Northrop Agreement	$ 7.8