CONSOLIDATED CONDENSED BALANCE SHEETS (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Accounts receivable, allowance for doubtful accounts (in dollars)	$ 4.2	$ 3.5
Preferred Stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred Stock, shares authorized	100,000us-gaap_PreferredStockSharesAuthorized	100,000us-gaap_PreferredStockSharesAuthorized
Preferred Stock, shares issued	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Preferred Stock, shares outstanding	0us-gaap_PreferredStockSharesOutstanding	0us-gaap_PreferredStockSharesOutstanding
Common Stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common Stock, shares authorized	240,000,000us-gaap_CommonStockSharesAuthorized	240,000,000us-gaap_CommonStockSharesAuthorized
Common Stock, shares issued	90,242,407us-gaap_CommonStockSharesIssued	90,244,840us-gaap_CommonStockSharesIssued
Common Stock, shares outstanding	90,242,407us-gaap_CommonStockSharesOutstanding	90,244,840us-gaap_CommonStockSharesOutstanding
Non-voting Common Stock
Common Stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common Stock, shares authorized	7,125,000	7,125,000
Common Stock, shares issued	0	0
Common Stock, shares outstanding	0	0
Class C Common Stock
Common Stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common Stock, shares authorized	20,000,000	20,000,000
Common Stock, shares issued	0	0
Common Stock, shares outstanding	0	0

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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