Income taxes (Tables)

12 Months Ended

Dec. 31, 2012

Income taxes

Schedule of income taxes by jurisdiction

	2012			2011			2010
U.S. federal:
Current	$	1,651		$	1,971		$	214
Deferred		1,189			2,261			(10,360	)
Total U.S. federal	$	2,840		$	4,232		$	(10,146	)
U.S. state and local:
Current	$	327		$	1,092		$	1,193
Deferred		(202	)		(1,260	)		50
Total U.S. state and local	$	125		$	(168	)	$	1,243

Schedule of reconciliation of tax rates

	2012			2011			2010
Federal statutory rate		34.0	%		34.0	%		34.0	%
State and local		1.1			(0.7	)		16.7
Stock options		(2.6	)		1.9			4.0
Non-controlling interests		(2.2	)		(2.0	)		(2.6	)
Valuation allowance		—			—			(172.9	)
Other		(3.3	)		3.8			(2.6	)
Income taxes		27.0	%		37.0	%		(123.4	)%

Schedule of deferred tax assets and liabilities

	2012			2011
Deferred tax assets:
Net operating loss carryforwards	$	1,917		$	3,735
Outside basis differences for U.S. partnerships		3,289			3,524
Stock options		2,086			1,397
Deferred revenue		873			1,014
Deferred compensation		340			407
State taxes		5			—
Other		347			455
Valuation allowance		(1,669	)		(1,822	)
Net deferred tax assets		7,188			8,710
Deferred tax liabilities:
Intangible assets		(1,539	)		(1,202	)
State taxes		—			(926	)
Property and equipment		(189	)		(133	)
Net deferred tax liabilities		(1,728	)		(2,261	)
Net deferred taxes	$	5,460		$	6,449

Summary of changes in uncertain tax positions

	Uncertain Tax Positions
Balance, December 31, 2010	$	106
Additions for current period tax positions		286
Balance, December 31, 2011 and 2012	$	392

Schedule of changes in the valuation allowance

	Valuation Allowance
Balance, December 31, 2009	$	14,989
Additions charged to operations		400
Decrease credited to operations		(12,280	)
Balance, December 31, 2010		3,109
Decrease credited to operations		(1,287	)
Balance, December 31, 2011		1,822
Additions charged to operations		51
Decrease credited to operations		(204	)
Balance, December 31, 2012	$	1,669