Significant Concentrations of Risk (Details)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Boeing [Member] | Revenue [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage	60.00%	79.00%	79.00%
Boeing [Member] | Accounts Receivable [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage	16.00%	40.00%	36.00%
Airbus [Member] | Revenue [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage	23.00%	16.00%	16.00%
Airbus [Member] | Accounts Receivable [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage	37.00%	41.00%	48.00%
Domestic Destination [Member]
Concentration Risk [Line Items]
Number of employees	9,700
percentage of represented workers	83.00%
U.K. [Member]
Concentration Risk [Line Items]
Number of employees	3,800
U.K. [Member] | Belfast
Concentration Risk [Line Items]
percentage of represented workers	84.00%
U.K. [Member] | Prestwick [Member]
Concentration Risk [Line Items]
percentage of represented workers	57.00%
Malaysia [Member]
Concentration Risk [Line Items]
Number of employees	700
France [Member]
Concentration Risk [Line Items]
Number of employees	100
Morocco [Member]
Concentration Risk [Line Items]
percentage of represented workers	43.00%