Inventories (Details) $ in Thousands	Dec. 31, 2016 USD ($) shipset	Dec. 31, 2015 USD ($)
Schedule of Inventory [Line Items]
Merchandise for resale	$ 158,618	$ 161,691
Raw materials	20,592	24,721
Progress payments	28,824	28,812
Other work in process (including certain general stock materials)	22,096	26,588
Finished goods	25,309	23,205
Total	393,814	385,747
Inventories include amounts associated with matters such as contract changes, negotiated settlements and claims for unanticipated contract costs	3,600	7,100
Segment work in progress	22,096	26,588
Aerospace acquisition
Schedule of Inventory [Line Items]
General and administrative costs in inventory, incurred	13,000	15,800
General and administrative costs in inventory, remaining	11,000	13,500
Distribution
Schedule of Inventory [Line Items]
Consignment inventory	6,400	6,500
K-MAX® program
Schedule of Inventory [Line Items]
Other work in process (including certain general stock materials)	15,900	14,900
Segment work in progress	15,900	14,900
SH-2G(I) [Member]
Schedule of Inventory [Line Items]
Other work in process (including certain general stock materials)	7,200	9,000
Segment work in progress	7,200	9,000
Contract sale inventory	3,800
A-10 program [Member]
Schedule of Inventory [Line Items]
Backlog	$ 5,300
Remaining A-10 shipsets	11
Total program inventory	$ 12,800
Inventory associated with nonrecurring costs	$ 8,700
Number of shipsets delivered | shipset	162
Shipsets under program of record | shipset	242
U.S. Government contracts
Schedule of Inventory [Line Items]
U.S. Government, net of progress payments of $28,824 and $28,812 in 2016 and 2015, respectively	$ 85,779	88,345
Commercial and other government contracts
Schedule of Inventory [Line Items]
Commercial and other government contracts	$ 81,420	$ 61,197