Income Taxes - Net Deferred Tax Assets (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Deferred Income Taxes [Abstract]
Deferred tax assets - current	$ 11,610	$ 12,245
Deferred tax assets - noncurrent	1,695	5,092
Deferred tax liabilities - current	(53)	(93)
Deferred tax liabilities - noncurrent	(7,251)	(17,588)
Net deferred tax assets (liabilities)	6,001	(344)
Valuation allowance	$ 2,819	$ 2,081