Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Statement of Comprehensive Income [Abstract]
Net Income		$ 10.1	$ 10.2	$ 36.0	$ 45.6
Defined benefit pension plans:
Net gain (loss) and prior service cost		(0.8)	1.2	(0.8)	1.2
Amortization of prior service credit included in net periodic pension cost	[1]	(0.3)	(0.3)	(0.6)	(0.6)
Amortization of net loss included in net periodic pension cost	[1]	2.5	0.3	3.6	2.2
Income taxes related to other comprehensive income		(0.6)	(0.4)	(0.9)	(1.1)
Other Comprehensive Income		0.8	0.8	1.3	1.7
Comprehensive Income		10.9	11.0	37.3	47.3
Comprehensive income attributable to noncontrolling interest		(0.3)	(1.0)	(0.9)	(1.4)
Comprehensive income attributable to A&B		$ 10.6	$ 10.0	$ 36.4	$ 45.9

[1] These accumulated other comprehensive income components are included in the computation of net periodic pension cost (see Note 9 for additional details).