Retirement Benefit Plan - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Shares fully vested, Description			Shares allocated to a participant’s account are fully vested after three years of credited service, or in the event(s) of reaching age 65, death or disability while an active employee of the Company.
Shares fully vested after credited service			3 years
Common stock shares outstanding including ESOP	103,560,969		103,560,969		103,659,731
Company's stock held by ESOP	65,097,822		65,097,822		70,328,237
Direct Costs of Contracts and Selling, General and Administrative Expense
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
ESOP contribution expense	$ 13.5	$ 13.4	$ 26.5	$ 26.5