STATEMENTS OF CHANGES IN MEMBERS' EQUITY (USD $) In Thousands, unless otherwise specified	Total	Accumulated Other Comprehensive Income	Members' Equity
BALANCE at Dec. 31, 2009	$ 57,047	$ (132)	$ 57,179
Increase (Decrease) in Stockholders' Equity
Net income	5,009		5,009
Member distributions	(10,998)		(10,998)
Issuance of membership units	141		141
Pension liability adjustment	(12)	(12)
BALANCE at Dec. 31, 2010	51,187	(144)	51,331
Increase (Decrease) in Stockholders' Equity
Net income	5,338		5,338
Member distributions	(9,945)		(9,945)
Pension liability adjustment	(4)	(4)
BALANCE at Dec. 31, 2011	46,576	(148)	46,724
Increase (Decrease) in Stockholders' Equity
Net income	5,649		5,649
Member distributions	(9,450)		(9,450)
Pension liability adjustment	(31)	(31)
BALANCE at Dec. 31, 2012	$ 42,744	$ (179)	$ 42,923