Other Financial Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2022	Mar. 31, 2021	Sep. 30, 2022	Mar. 03, 2022	Sep. 30, 2021
Accrued expenses and other current liabilities
Accrued salaries and benefits	$ 639,200		$ 639,200		$ 661,800
Accrued contract costs	1,228,500		1,228,500		1,202,100
Other accrued expenses	351,300		351,300		310,300
Total accrued expenses	2,218,969		2,218,969		$ 2,174,200		$ 2,174,201
Restructuring costs	73,292	$ 8,746	76,663	$ 21,784
Accrued restructuring expenses	600	$ 3,700	600	3,700
Restructuring cost related to margins and delivery efficiency			7,600
Dividend paid per share in cash						$ 0.15
Accrued and unpaid dividend	21,800		21,800
Foreign Currency Translation Adjustments
Accrued expenses and other current liabilities
Amounts reclassified from accumulated other comprehensive (loss) income	19,500		19,500
Personnel and other costs
Accrued expenses and other current liabilities
Restructuring costs			5,400	16,800
Real estate costs
Accrued expenses and other current liabilities
Restructuring costs			2,200	$ 5,000
Facility Closing [Member] | RUSSIAN FEDERATION
Accrued expenses and other current liabilities
Restructuring costs	69,100		69,100
Accrued restructuring expenses	5,800		5,800
Facility Closing [Member] | RUSSIAN FEDERATION | Foreign Currency Translation Adjustments
Accrued expenses and other current liabilities
Amounts reclassified from accumulated other comprehensive (loss) income			19,500
Professional liability accrual
Accrued expenses and other current liabilities
Accrued contract costs	$ 742,300		$ 742,300				$ 736,400