Subsequent Events - Additional Information (Details)		3 Months Ended								12 Months Ended
	Jan. 03, 2022 USD ($) Location employee	Dec. 31, 2021 USD ($)	Sep. 30, 2021 USD ($)	Jun. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2021 USD ($) Location $ / shares	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Feb. 18, 2022 USD ($)	Jan. 06, 2022 USD ($)
Subsequent Event [Line Items]
Sale agreement amount		$ 800,000				$ 800,000				$ 800,000	$ 800,000
Number of locations | Location										10,300
Revenue		$ 4,803,209,000	$ 4,818,849,000	$ 4,783,738,000	$ 4,464,714,000	$ 4,251,594,000	$ 4,370,086,000	$ 3,823,227,000	$ 4,092,526,000	$ 18,870,510,000	16,537,433,000	$ 17,522,234,000
Principal amount outstanding of receivables sold at period end											800,000
Acquisition costs										3,655,000	$ 39,817,000	$ 31,254,000
KDG
Subsequent Event [Line Items]
Pro forma revenue										19,918,700
Pro forma net income (loss)										$ 19,918,700
Pro forma net income (loss) per share - diluted (in dollars per share) | $ / shares										$ 6.01
Subsequent Event
Subsequent Event [Line Items]
Sale agreement amount	$ 200,000,000												$ 1,000,000,000
Subsequent Event | Senior Notes Due 2025
Subsequent Event [Line Items]
Debt instrument, stated percentage														1.75%
Debt instrument, face amount														$ 500,000
Issuance percent														99.721%
Subsequent Event | Senior Notes Due 2032
Subsequent Event [Line Items]
Debt instrument, stated percentage														2.75%
Debt instrument, face amount														$ 500,000
Issuance percent														98.81%
Subsequent Event | KDG
Subsequent Event [Line Items]
Consideration transferred	$ 1,309,000
Number of employees | employee	1,700
Number of locations | Location	220
Revenue	$ 1,100,000,000
Cash acquired from acquisition	30,000
Principal amount outstanding of receivables sold at period end	200,000
Payments to acquire businesses	109,000
Goodwill, expected to be tax deductible	261,000
Acquisition costs	$ 7,000