Investments in Marketable Securities (Tables)

6 Months Ended

Jun. 30, 2026

Investments, Debt and Equity Securities [Abstract]

Marketable Securities

Marketable securities at June 30, 2026 and December 31, 2025 consisted of the following:


						UNREALIZED				UNREALIZED				FAIR
At June 30, 2026		COST				GAINS				LOSSES				VALUE
Marketable debt securities
U.S. tax-exempt securities		$	269.1			$	2.3			$	.1			$	271.3
U.S. taxable municipal / non-U.S. provincial bonds			433.5				1.2				1.1				433.6
U.S. corporate securities			979.5				2.3				3.6				978.2
U.S. government securities			471.1								4.4				466.7
Non-U.S. corporate securities			630.4				2.2				1.8				630.8
Non-U.S. government securities			258.1				.6				.7				258.0
Other debt securities			214.4				.5				.7				214.2
Marketable equity securities			10.0								3.2				6.8
Total marketable securities		$	3,266.1			$	9.1			$	15.6			$	3,259.6


						UNREALIZED				UNREALIZED				FAIR
At December 31, 2025		COST				GAINS				LOSSES				VALUE
Marketable debt securities
U.S. tax-exempt securities		$	341.0			$	3.6			$	.1			$	344.5
U.S. taxable municipal / non-U.S. provincial bonds			417.7				4.2				.3				421.6
U.S. corporate securities			931.7				8.7				.1				940.3
U.S. government securities			433.9				2.5				.2				436.2
Non-U.S. corporate securities			634.8				5.4				.5				639.7
Non-U.S. government securities			212.8				1.3				.3				213.8
Other debt securities			206.4				1.6				.2				207.8
Marketable equity securities			10.0								6.2				3.8
Total marketable securities		$	3,188.3			$	27.3			$	7.9			$	3,207.7

Marketable Debt Securities Continuous Unrealized Losses

Marketable debt securities with continuous unrealized losses and their related fair values were as follows:


		June 30, 2026								December 31, 2025
		LESS THAN				TWELVE MONTHS				LESS THAN				TWELVE MONTHS
		TWELVE MONTHS				OR GREATER				TWELVE MONTHS				OR GREATER
Fair value		$	1,584.2			$	36.3			$	298.5			$	75.5
Unrealized losses			12.1				.3				1.0				.7

Contractual Maturities on Debt Securities

Contractual maturities on marketable debt securities at June 30, 2026 were as follows:


		AMORTIZED				FAIR
		COST				VALUE
Within one year		$	641.4			$	642.5
One to five years			2,603.9				2,599.4
Six to ten years			5.9				5.9
More than ten years			4.9				5.0
		$	3,256.1			$	3,252.8