Income Taxes - Deferred Income Tax Assets and Liabilities (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Deferred Income Taxes [Abstract]
Deferred tax assets - current	$ 15,114	$ 12,245
Deferred tax assets - noncurrent	1,751	5,092
Deferred tax liabilities - current	(9)	(93)
Deferred tax liabilities - noncurrent	(8,931)	(17,588)
Net deferred tax assets (liabilities)	7,925	(344)
Valuation allowance	2,723	2,081
Deferred tax assets:
Accrued liabilities and reserves	15,804	13,239
Revenue recognition	340	3,707
Tax credit and loss carryforwards	8,063	8,497
Fixed assets and intangibles	546	765
Unrealized investment	765	2,538
Stock compensation	2,151	1,815
Other assets	1,501	665
Gross deferred tax assets	29,170	31,226
Valuation allowance	2,723	2,081
Net deferred tax assets	26,447	29,145
Deferred tax liabilities:
Fixed assets and intangibles	(17,965)	(20,697)
Revenue recognition	(19)	(4,991)
Other liabilities	(538)	(3,801)
Total deferred tax liabilities	$ (18,522)	$ (29,489)