Segments - Schedule of Selected Financial Information for Each Reportable Segment and Reconciliation of EBITDAP to Operating Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Mar. 31, 2021
Segment Reporting Information [Line Items]
Net sales to external customers	$ 396,646	$ 495,077
Segment profit and reconciliation to consolidated income before income taxes:
Adjusted EBITDAP	60,218	38,452
Reconciliation of segment profit to income (loss) before income taxes
Depreciation and amortization	(15,431)	(28,602)
Interest expense and other, net	(38,558)	(34,957)
Corporate expenses	(16,953)	(18,061)
Share-based compensation expense	(2,247)	(2,786)
Loss on sale of assets and businesses	(5,969)
Amortization of acquired contract liabilities	1,214	10,987
Non-service defined benefit expense (income)	(1,722)	12,416
Debt extinguishment loss	(9,689)
Impairment of long-lived assets		(252,382)
Loss before income taxes	(29,137)	(274,933)
Total capital expenditures	2,112	7,723
Total assets	1,883,493		$ 2,450,935
Systems & Support [Member]
Segment Reporting Information [Line Items]
Intersegment sales (eliminated in consolidation)	8	1,872
Reconciliation of segment profit to income (loss) before income taxes
Amortization of acquired contract liabilities	1,202	3,719
Aerospace Structures [Member]
Segment Reporting Information [Line Items]
Intersegment sales (eliminated in consolidation)	11	815
Reconciliation of segment profit to income (loss) before income taxes
Amortization of acquired contract liabilities	12	7,268
Corporate & Eliminations [Member]
Segment Reporting Information [Line Items]
Net sales to external customers	(19)	(2,687)
Reconciliation of segment profit to income (loss) before income taxes
Depreciation and amortization	(768)	(856)
Total capital expenditures	358	411
Total assets	211,881
Operating Segments [Member] | Systems & Support [Member]
Segment Reporting Information [Line Items]
Net sales to external customers	258,405	238,015
Segment profit and reconciliation to consolidated income before income taxes:
Adjusted EBITDAP	42,848	30,068
Reconciliation of segment profit to income (loss) before income taxes
Depreciation and amortization	(8,504)	(8,356)
Total capital expenditures	1,102	6,283
Total assets	1,443,582
Operating Segments [Member] | Aerospace Structures [Member]
Segment Reporting Information [Line Items]
Net sales to external customers	138,241	257,062
Segment profit and reconciliation to consolidated income before income taxes:
Adjusted EBITDAP	17,370	8,384
Reconciliation of segment profit to income (loss) before income taxes
Depreciation and amortization	(6,159)	(19,390)
Total capital expenditures	652	$ 1,029
Total assets	$ 228,030