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Supplemental Disclosures of Cash Flow Information - Additional Information (Detail) - Qualified Contributory Savings and Thrift 401(k) Plan [Member] - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Defined Benefit Plan Disclosure [Line Items]
Matching contributions by employer, percentage	100.00%
Percentage of eligible compensation for matching contributions by employer	5.00%
Matching contributions vesting schedule	5 years
Contribution expense to plan	$ 59.8	$ 51.8
Employer match on eligible compensation	5.00%
Increased net cash provided by operating activities		69.1
Decreased net cash used by investing activities		$ 69.1

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Decreased net cash used by investing activities.

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Defined benefit plan percentage of eligible compensation for matching contributions by employer.

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Increased net cash provided by operating activities.

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Matching contributions vesting schedule.

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Amount of cost for defined contribution plan.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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