ACQUISITION OF FOX ENERGY CENTER (Details) (USD $) In Millions, unless otherwise specified		1 Months Ended
Nov. 30, 2013 Senior Notes, 4.752% due 2044	Mar. 31, 2013 Fox Energy Company LLC MW
Acquisitions
Amount paid for the acquisition		$ 391.6
Capacity of Fox Energy Center (in megawatts)		593
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
Contracted capacity under a power purchase agreement (in megawatts)		500
Contract termination fee related to tolling arrangement		$ 50.0
Amortization period of regulatory asset		9 years
Interest rate stated percentage	4.752%

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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Interest rate stated in the contractual debt agreement.

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