Segment Data (Details 1) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Dec. 31, 2013	Jun. 30, 2013
Segment Reporting Information [Line Items]
Segment Assets	$ 3,808,200	$ 3,301,039
Goodwill from TMB acquisition	242,363
Allegheny Technologies Incorporated [Member]
Segment Reporting Information [Line Items]
Goodwill from TMB acquisition	242,363
Industrial [Member]
Segment Reporting Information [Line Items]
Segment Assets	1,329,156	1,190,026
Goodwill from TMB acquisition	0
Infrastructure [Member]
Segment Reporting Information [Line Items]
Segment Assets	1,834,544	1,522,470
Goodwill from TMB acquisition	0
Corporate Segment [Member]
Segment Reporting Information [Line Items]
Segment Assets	$ 402,137	$ 588,543