Business Segments (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Segment Reporting Information [Line Items]
Net revenues:	$ 1,526.6	$ 1,376.1
Percent change in net revenues	10.90%
Gross profit:	$ 1,030.1	936.0
Percent change in gross profit	10.10%
Operating profit	$ 476.9	424.4
Percent change in operating profit	12.40%
Long-lived assets:	$ 210.1	206.7
Percent change in long-lived assets	1.60%
Corporate
Segment Reporting Information [Line Items]
Unallocated corporate general and administrative expenses	$ 55.8	49.8
Application Software
Segment Reporting Information [Line Items]
Net revenues:	$ 631.5	576.6
Percent change in net revenues	9.50%
Gross profit:	$ 437.8	398.7
Percent change in gross profit	9.80%
Operating profit	$ 173.8	153.7
Percent change in operating profit	13.10%
Long-lived assets:	$ 135.8	126.7
Percent change in long-lived assets	7.20%
Network Software & Systems
Segment Reporting Information [Line Items]
Net revenues:	$ 368.7	314.2
Percent change in net revenues	17.30%
Gross profit:	$ 302.4	256.4
Percent change in gross profit	17.90%
Operating profit	$ 145.4	114.1
Percent change in operating profit	27.40%
Long-lived assets:	$ 28.5	27.8
Percent change in long-lived assets	2.50%
Measurement & Analytical Solutions
Segment Reporting Information [Line Items]
Net revenues:	$ 392.4	369.6
Percent change in net revenues	6.20%
Gross profit:	$ 217.6	218.2
Percent change in gross profit	(0.30%)
Operating profit	$ 115.9	121.5
Percent change in operating profit	(4.60%)
Long-lived assets:	$ 32.5	33.9
Percent change in long-lived assets	(4.10%)
Process Technologies
Segment Reporting Information [Line Items]
Net revenues:	$ 134.0	115.7
Percent change in net revenues	15.80%
Gross profit:	$ 72.3	62.7
Percent change in gross profit	15.30%
Operating profit	$ 41.8	35.1
Percent change in operating profit	19.10%
Long-lived assets:	$ 13.3	$ 18.3
Percent change in long-lived assets	(27.30%)