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USD ($)

USD ($) / shares
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       NOTES&amp;#160;AND OTHER LONG-TERM RECEIVABLES&lt;/font&gt;&lt;/b&gt;
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       Investments, notes and other long-term receivables were
       $6.2&amp;#160;million and $19.3&amp;#160;million at December&amp;#160;31,
       2010 and 2009, respectively. Included as investments, notes and
       other long-term receivables was an investment accounted for
       using the equity method of accounting of $13.1&amp;#160;million as
       of December&amp;#160;31, 2009 relating to a venture with Baltimore
       Gas&amp;#160;&amp;#038; Electric (a subsidiary of Constellation Energy).
       This venture designs, constructs, owns, operates, leases and
       maintains facilities to produce chilled water for sale to
       customers for use in air conditioning commercial properties. As
       a result of our discounted cash flow analysis, an impairment
       charge of $7.0&amp;#160;million was recognized in 2008, to
       write-down the carrying value of this investment to its
       estimated fair value. We recorded this
       &lt;font style="white-space: nowrap"&gt;other-than-temporary&lt;/font&gt;
       decline in fair value as a component of &amp;#8220;Cost of
       Sales&amp;#8221; on the Consolidated Statements of Operations. In
       2009, the venture, using its own cash and cash from additional
       capital contributions, acquired its outstanding bonds in the
       principal amount of $25.0&amp;#160;million. As a result of this, we
       were required to make an additional capital contribution of
       $8.0&amp;#160;million to the venture. In January 2010, this venture,
       including our investment, was sold to a third party. As a result
       of this sale, we received $17.7&amp;#160;million for our 40%
       interest and recognized a pretax gain of $4.5&amp;#160;million,
       which gain is included in our United States facilities services
       segment and classified as a component of &amp;#8220;Cost of
       Sales&amp;#8221; on the Consolidated Statements of Operations.
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       Additionally in June 2010, we sold our equity interest in a
       Middle East venture, which performed facilities services, to our
       partner in the venture. As a result of this sale, we received
       $7.9&amp;#160;million and recognized a pretax gain in this amount,
       which is classified as a &amp;#8220;Gain on sale of equity
       investment&amp;#8221; on the Consolidated Statements of Operations.
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