Valuation and Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Allowance for Doubtful Accounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of year	$ 1,837		$ 1,952		$ 2,134
Charged to costs and expenses	30		4		202
Deductions / net charge offs	(1,783)	[1]	(119)	[1]	(384)	[1]
Balance at end of year	84		1,837		1,952
Valuation Allowance of Deferred Tax Assets [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Charged to costs and expenses	986
Balance at end of year	$ 986

[1] Represents write-off of bad debts net of recoveries