Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Per Share data	Jun. 30, 2011	Dec. 31, 2010
Current assets:
Allowance for doubtful accounts receivable	$ 4,679	$ 5,481
Deferred debt issuance cost, accumulated amortization	$ 7,883	$ 6,882
Stockholders' equity
Trust shares, par value	$ 0	$ 0
Trust shares, authorized	500,000	500,000
Trust shares, issued	46,725	46,725
Trust shares, outstanding	46,725	46,725

Carrying amount of accumulated amortization of long-term deferred finance costs capitalized at the end of the reporting period.

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