ACQUISITION OF FOX ENERGY CENTER (Details) (Fox Energy Company LLC, USD $) In Millions, unless otherwise specified	Mar. 31, 2013 MW
Fox Energy Company LLC
Acquisitions
Amortization period of regulatory asset	9 years
Capacity of Fox Energy Center (in megawatts)	593
Contracted capacity under a power purchase agreement (in megawatts)	500
Contract termination fee related to tolling arrangement	$ 50.0
Amount paid for the acquisition of Fox Energy Company LLC	391.6
Assets acquired
Inventories - materials and supplies	3.0
Other current assets	0.4
Property, plant, and equipment	374.4
Other long-term assets	15.6
Total assets acquired	393.4
Liabilities assumed
Accounts payable	1.8
Total liabilities assumed	$ 1.8

The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

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