Schedule II - 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
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of period	$ 472		$ 602		$ 474
Additions charged to costs and expenses	200		208		231
Additions charged to other accounts	9	[1]	7	[1]	(3)	[1]
Deductions	(118)	[2]	(345)	[2]	(100)	[2]
Balance at end of period	563		472		602
Valuation allowance on deferred tax assets
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of period	97,376		50,746		28,201
Additions charged to costs and expenses	13,015		6,093		11,795
Additions charged to other accounts	389	[3]	40,537	[3]	10,750	[3]
Deductions	0		0		0
Balance at end of period	$ 110,780		$ 97,376		$ 50,746

[1] Foreign currency translation adjustments.

[2] Bad debts written off, net of recoveries.

[3] This amount was charged to income tax expense, but is fully offset by the income tax benefit generated when recording the corresponding deferred tax asset.