Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2011

Summary of Significant Accounting Policies [Abstract]

Allowance for Doubtful Accounts Receivable

Additions, deductions and balances for allowance for doubtful accounts for 2011, 2010 and 2009 are as follows (in thousands):

	2011		2010		2009
Balance at beginning of year	$	2,885	$	1,191	$	3,123
Additions:
Charged to costs and expense	6,209		4,756		3,289
Recovery of previous write-offs	2,034		852		1,316
Uncollectible receivables written off	8,113		3,914		6,537
Balance at end of year	$	3,015	$	2,885	$	1,191