Debt - Selected Information about Debt Issues (Detail) - USD ($)	May 19, 2022	Sep. 30, 2022	Sep. 15, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Long-term debt, par value, gross		$ 1,815,612,000
Current maturity of long-term debt, par value		165,612,000
Par Value		1,650,000,000
Total short-term debt, par value		435,612,000
Total debt, par value		2,085,612,000
Unamortized discount & issuance costs, noncurrent		(22,638,000)
Unamortized discount & issuance costs, current maturities		(185,000)
Unamortized discount & issuance costs, long-term debt		(22,453,000)
Unamortized discount & issuance costs, current		(875,000)
Total debt, unamortized discount & issuance costs,		(23,328,000)
Long-term debt, net, book value		1,792,974,000		$ 1,696,246,000
Current maturity of long-term debt, book value		165,427,000		149,752,000
Long-term debt		1,627,547,000		1,546,494,000
Total short-term debt, book value		434,737,000		479,644,000
Total debt, book value		2,062,284,000		2,026,138,000
Long-term debt, gross, fair value		1,613,304,000
Current maturity of term loan, fair value		167,781,000
Long-term debt, net, fair value		1,445,523,000
Total short-term debt, fair value		437,091,000
Total debt, fair value		1,882,614,000
Commercial Paper
Debt Instrument [Line Items]
Total short-term debt, par value		270,000,000
Unamortized discount & issuance costs, current		(690,000)
Total short-term debt, book value		269,310,000		329,892,000
Total short-term debt, fair value		$ 269,310,000
Senior Notes Due 2023
Debt Instrument [Line Items]
Coupon Rate		7.875%
Long-term debt, par value, gross		$ 165,612,000
Unamortized discount & issuance costs, noncurrent		(185,000)
Debt		165,427,000		165,216,000
Long-term debt, gross, fair value		$ 167,781,000
Senior Notes Due 2022
Debt Instrument [Line Items]
Coupon Rate		3.80%	3.80%
Debt				149,752,000
Debt repayment	$ 300,000,000
Senior Notes Due 2022 | Consolidation Eliminations | Subsidiaries
Debt Instrument [Line Items]
Long-term debt, net, book value		$ 150,000,000
Senior Notes Due 2028
Debt Instrument [Line Items]
Coupon Rate		4.55%
Long-term debt, par value, gross		$ 550,000,000
Unamortized discount & issuance costs, noncurrent		(4,562,000)
Debt		545,438,000		544,949,000
Long-term debt, gross, fair value		$ 526,702,000
Senior Notes Due 2030
Debt Instrument [Line Items]
Coupon Rate		2.15%
Long-term debt, par value, gross		$ 400,000,000
Unamortized discount & issuance costs, noncurrent		(3,891,000)
Debt		396,109,000		395,778,000
Long-term debt, gross, fair value		$ 310,560,000
Senior Notes Due June 15 2032
Debt Instrument [Line Items]
Coupon Rate		4.80%
Long-term debt, par value, gross		$ 250,000,000
Unamortized discount & issuance costs, noncurrent		(4,616,000)
Debt		245,384,000		0
Long-term debt, gross, fair value		$ 231,700,000
Junior Subordinated Debentures Due 2057
Debt Instrument [Line Items]
Coupon Rate		5.275%
Long-term debt, par value, gross		$ 125,000,000
Unamortized discount & issuance costs, noncurrent		(1,594,000)
Debt		123,406,000		123,396,000
Long-term debt, gross, fair value		$ 124,016,000
Junior Subordinated Debentures Due 2061
Debt Instrument [Line Items]
Coupon Rate		4.25%
Long-term debt, par value, gross		$ 325,000,000
Unamortized discount & issuance costs, noncurrent		(7,790,000)
Debt		317,210,000		$ 317,155,000
Long-term debt, gross, fair value		$ 252,545,000