Revenue and Geographic Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Revenues	$ 784,459	$ 761,608	$ 735,994
Long-Lived Assets	$ 668,610	$ 447,215
Revenues, Percentage	100.00%	100.00%	100.00%
Deferred Tax Assets, Net	$ 39,800	$ 35,200
U.S. Government contracts
Disaggregation of Revenue [Line Items]
Revenues	220,800	244,300	$ 281,300
North America [Member]
Disaggregation of Revenue [Line Items]
Revenues	412,025	438,638	485,856
Europe [Member]
Disaggregation of Revenue [Line Items]
Revenues	148,473	164,921	167,176
Middle East [Member]
Disaggregation of Revenue [Line Items]
Revenues	170,835	114,110	51,565
Asia [Member]
Disaggregation of Revenue [Line Items]
Revenues	34,424	19,326	16,998
Oceania [Domain]
Disaggregation of Revenue [Line Items]
Revenues	11,156	14,598	8,739
Segment, Geographical, Groups of Countries, Group Six [Member]
Disaggregation of Revenue [Line Items]
Revenues	7,546	10,015	$ 5,660
UNITED STATES
Disaggregation of Revenue [Line Items]
Long-Lived Assets	493,490	249,935
GERMANY
Disaggregation of Revenue [Line Items]
Long-Lived Assets	167,939	157,504
UNITED KINGDOM
Disaggregation of Revenue [Line Items]
Long-Lived Assets	0	32,834
CZECH REPUBLIC
Disaggregation of Revenue [Line Items]
Long-Lived Assets	5,747	5,753
MEXICO
Disaggregation of Revenue [Line Items]
Long-Lived Assets	796	1,189
NETHERLANDS
Disaggregation of Revenue [Line Items]
Long-Lived Assets	339	0
SWITZERLAND
Disaggregation of Revenue [Line Items]
Long-Lived Assets	235	0
HONG KONG
Disaggregation of Revenue [Line Items]
Long-Lived Assets	$ 64	$ 0
Transferred over Time [Member]
Disaggregation of Revenue [Line Items]
Revenues, Percentage	31.00%	39.00%	48.00%
Transferred at Point in Time [Member]
Disaggregation of Revenue [Line Items]
Revenues, Percentage	69.00%	61.00%	52.00%
Military and Defense, other than fuzes [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 180,400	$ 178,289	$ 190,264
Missile and Bomb Fuzes [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 248,482	$ 227,846	$ 195,751
Revenues, Percentage	32.00%	30.00%	27.00%
Commercial Aerospace [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 220,263	$ 280,987	$ 274,835
Medical
Disaggregation of Revenue [Line Items]
Revenues	70,010	28,652	28,962
Other
Disaggregation of Revenue [Line Items]
Revenues	$ 65,304	$ 45,834	$ 46,182
Original Equipment Manufacturer [Member]
Disaggregation of Revenue [Line Items]
Revenues, Percentage	56.00%	58.00%	56.00%
Aftermarket [Member]
Disaggregation of Revenue [Line Items]
Revenues, Percentage	12.00%	12.00%	17.00%
Time-and-materials Contract [Member] | Minimum [Member]
Disaggregation of Revenue [Line Items]
Revenue, Performance Obligation, Description of Timing	30
Time-and-materials Contract [Member] | Maximum [Member]
Disaggregation of Revenue [Line Items]
Revenue, Performance Obligation, Description of Timing	60 days
Fixed-price Contract [Member] | Minimum [Member]
Disaggregation of Revenue [Line Items]
Revenue, Performance Obligation, Description of Timing	30
Fixed-price Contract [Member] | Maximum [Member]
Disaggregation of Revenue [Line Items]
Revenue, Performance Obligation, Description of Timing	90 days