Transactions with Related Party (Details) (USD $)	12 Months Ended			1 Months Ended	12 Months Ended			1 Months Ended	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2005 SHG person	Dec. 31, 2011 SHG person	Dec. 31, 2010 SHG	Dec. 31, 2009 SHG	Feb. 28, 2006 Laurel Y	Dec. 31, 2011 Laurel	Dec. 31, 2010 Laurel	Dec. 31, 2009 Laurel
Transactions with Related Party
Number of directors serving as chief executive officer of related entity				1	1
Senior subordinated notes purchased in open market				$ 10,000,000
Face rate of senior subordinated notes (as a percent)				11.00%	11.00%
Effective yield on senior subordinated notes (as a percent)				11.10%	11.10%
Investment in senior subordinated notes of related party	6,500,000	6,500,000	6,500,000		6,500,000	6,500,000
Interest income related to senior subordinated notes	721,000	720,000	720,000		721,000	720,000	720,000
Period of master lease agreement (in years)								15
Rental income	4,264,000	4,160,000	4,058,000						4,264,000	4,160,000	4,058,000
Straight-line rental income	238,000	342,000	443,000						238,000	342,000	443,000
Straight-line rental income receivable from subsidiaries	$ 3,060,000	$ 2,822,000							$ 3,060,000	$ 2,822,000