Consolidated Statements Of Income (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2012	Mar. 31, 2011
Consolidated Statements Of Income [Abstract]
NET SALES	$ 539.9	$ 464.2	$ 1,385.1	$ 1,191.5
Cost of sales	434.8	391.1	1,114.5	1,019.5
Gross profit	105.1	73.1	270.6	172.0
Selling, general and administrative expenses	41.5	37.9	115.3	109.9
Acquisition related costs	7.9		11.7	0.7
Operating income	55.7	35.2	143.6	61.4
Interest expense	(5.6)	(4.4)	(18.4)	(12.9)
Other income, net	1.7	1.1	1.4	5.7
Income before income taxes	51.8	31.9	126.6	54.2
Income tax expense	18.8	3.1	46.0	8.4
Net income	33.0	28.8	80.6	45.8
Less: Net income attributable to noncontrolling interest		(0.2)	(0.3)	(0.3)
NET INCOME ATTRIBUTABLE TO CARPENTER	$ 33.0	$ 28.6	$ 80.3	$ 45.5
EARNINGS PER COMMON SHARE:
Basic	$ 0.69	$ 0.64	$ 1.76	$ 1.02
Diluted	$ 0.69	$ 0.64	$ 1.75	$ 1.02
WEIGHTED AVERAGE COMMON SHARES OUTSTANDING:
Basic	47.2	44.1	45.3	44.1
Diluted	47.9	44.7	46.0	44.6
Cash dividends per common share	$ 0.18	$ 0.18	$ 0.54	$ 0.54