Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Statement of Cash Flows [Abstract]
Cash Flows from (used in) Operating Activities:	$ 69.4	$ (20.6)
Cash Flows from Investing Activities:
Capital expenditures for property, plant and equipment	(20.4)	(19.7)
Capital expenditures related to 1031 commercial property transactions	(1.3)	0.0
Proceeds from investment tax credits and grants related to Port Allen Solar Farm	0.0	4.5
Proceeds from disposal of property and other assets	5.1	8.2
Proceeds from disposals related to 1031 commercial property transactions	25.2	71.7
Payments for purchases of investments in affiliates	(18.1)	(9.0)
Proceeds from investments in affiliates	37.2	6.2
Change in restricted cash associated with 1031 transactions	(2.7)	(0.5)
Net cash provided by investing activities	25.0	61.4
Cash Flows from Financing Activities:
Proceeds from issuances of long-term debt	51.0	73.0
Payments of long-term debt and deferred financing costs	(136.9)	(43.4)
Proceeds from (payments of) line-of-credit agreements, net	(2.5)	(63.7)
Dividends paid	(4.9)	(3.9)
Distributions to non-controlling interest	(1.1)	0.0
Proceeds from issuance (repurchase) of capital stock and other, net	(0.5)	0.1
Net cash used in financing activities	(94.9)	(37.9)
Cash and Cash Equivalents:
Net increase (decrease) for the period	(0.5)	2.9
Balance, beginning of period	2.8	3.3
Balance, end of period	2.3	6.2
Other Cash Flow Information:
Interest paid	(14.3)	(14.8)
Income taxes paid	(3.6)	(11.0)
Other Non-cash Information:
Real estate exchanged for note receivable	0.0	3.6
Land contributed into real estate joint venture	9.6	0.0
Capital expenditures included in accounts payable and accrued expenses	$ 4.8	$ 3.1