Schedule II - Valuation and Qualifying Accounts (Details) (Allowance for Doubtful Accounts, USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Allowance for Doubtful Accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 161		$ 118		$ 97
Additions to Bad Debt Expense or Deferred Tax Asset	325		62		39
Charged to Other Accounts	0	[1]	0	[1]	0	[1]
Deductions	(14)	[1],[2]	(19)	[1],[2]	(18)	[1],[2]
Balance at End of Period	$ 472		$ 161		$ 118

[1]

[2] Deductions represent the actual write-off of accounts receivable balances.