Retirement Benefit Plan - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 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	103,730,134		103,659,731
Company's stock held by ESOP	68,787,554		70,328,237
Direct Costs of Contracts and Selling, General and Administrative Expense
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
ESOP contribution expense	$ 13.1	$ 13.2