Consolidated Statements of Partners' Capital (USD $) In Thousands, unless otherwise specified	Total	General partner	Class A limited partners	Accumulated other comprehensive loss
Balance at Dec. 31, 2011	$ 42,537	$ 81	$ 42,785	$ (329)
Allocation of net (loss):
Allocation of net income (loss)	(8)		(8)
Other comprehensive income
Change in pension and severance obligations	6			6
Balance at Mar. 31, 2012	42,535	81	42,777	(323)
Balance at Dec. 31, 2012	42,002	81	42,286	(365)
Allocation of net (loss):
Allocation of net income (loss)	(628)		(628)
Cash distributions:
Cash distributions	(150)		(150)
Other comprehensive income
Change in pension and severance obligations	7			7
Balance at Mar. 31, 2013	$ 41,231	$ 81	$ 41,508	$ (358)