Income taxes (Details 2) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Deferred Tax Assets [Abstract]
Provision for doubtful accounts	$ 1,020	$ 955
Accrued rent	1,748	1,688
Reserve for newsstand returns	139	52
Accrued compensation	11,161	9,620
Deferred royalty revenue	1,165	131
NOL/credit carryforwards	59,868	56,777
Depreciation	6,071	5,778
Amortization of intangible assets	7,756	8,987
Other	242	482
Total deferred tax assets	89,170	84,470
Deferred Tax Liabilities [Abstract]
Prepaid expenses	(293)	(624)
Amortization of intangible assets	(7,117)	(5,874)
Total deferred tax liabilities	(7,410)	(6,498)
Valuation allowance	(88,877)	(83,846)
Net Deferred Tax Liabilities	$ (7,117)	$ (5,874)