Schedule 5 Valuation and Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of year	$ 3,668	$ 3,639	$ 4,280
Provision expense	1,584	362	1,238
Amounts written off and other	(1,630)	(333)	(1,879)
Balance at end of year	$ 3,622	$ 3,668	$ 3,639