Consolidated Condensed Balance Sheets (Unaudited) (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Allowance for uncollectibles	$ 2.2	$ 2.1
Common equity, shares authorized	400,000,000us-gaap_CommonStockSharesAuthorized	400,000,000us-gaap_CommonStockSharesAuthorized
Common equity, par value	$ 1	$ 1
Common equity, shares outstanding	235,600,000us-gaap_CommonStockSharesOutstanding	234,900,000us-gaap_CommonStockSharesOutstanding
Tampa Electric Company [Member]
Allowance for uncollectibles	$ 1.5	$ 1.4

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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