Redeemable Preferred Stock (Details) (USD $)	3 Months Ended		12 Months Ended	0 Months Ended		3 Months Ended				3 Months Ended			3 Months Ended			12 Months Ended			30 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 1998	Aug. 24, 2012 Senior Redeemable Preferred Stock [Member]	May 16, 2012 Senior Redeemable Preferred Stock [Member]	Mar. 31, 2013 Senior Redeemable Preferred Stock [Member]	Mar. 31, 2012 Senior Redeemable Preferred Stock [Member]	Dec. 31, 2012 Senior Redeemable Preferred Stock [Member]	May 11, 2012 Senior Redeemable Preferred Stock [Member]	Mar. 31, 2013 Senior Redeemable Preferred Stock [Member] Toxford [Member]	Dec. 31, 2012 Senior Redeemable Preferred Stock [Member] Porter [Member]	Dec. 31, 2012 Senior Redeemable Preferred Stock [Member] Porter And Toxford [Member]	Mar. 31, 2013 Public Preferred Stock [Member]	Mar. 31, 2012 Public Preferred Stock [Member]	Jun. 30, 2006 Public Preferred Stock [Member]	Dec. 31, 2012 Public Preferred Stock [Member]	Dec. 31, 1991 Public Preferred Stock [Member]	Dec. 31, 1990 Public Preferred Stock [Member]	Jun. 30, 1995 Public Preferred Stock [Member] tranche	Mar. 31, 2013 Series A-1 Preferred Stock [Member] Senior Redeemable Preferred Stock [Member]	Dec. 31, 2012 Series A-1 Preferred Stock [Member] Senior Redeemable Preferred Stock [Member]	Aug. 24, 2012 Series A-1 Preferred Stock [Member] Senior Redeemable Preferred Stock [Member]	May 16, 2012 Series A-1 Preferred Stock [Member] Senior Redeemable Preferred Stock [Member]	Dec. 31, 2012 Series A-1 Preferred Stock [Member] Senior Redeemable Preferred Stock [Member] Porter And Toxford [Member]	Mar. 31, 2013 Series A-2 Preferred Stock [Member] Senior Redeemable Preferred Stock [Member]	Dec. 31, 2012 Series A-2 Preferred Stock [Member] Senior Redeemable Preferred Stock [Member]	Aug. 24, 2012 Series A-2 Preferred Stock [Member] Senior Redeemable Preferred Stock [Member]	May 16, 2012 Series A-2 Preferred Stock [Member] Senior Redeemable Preferred Stock [Member]	Dec. 31, 2012 Series A-2 Preferred Stock [Member] Senior Redeemable Preferred Stock [Member] Porter And Toxford [Member]	Mar. 15, 2011 Class A Common Stock [Member] Porter [Member]
Class of Stock [Line Items]
Preferred stock authorized (in shares)													6,000,000							1,250					1,750
Preferred stock par value (in dollar per share)													$ 0.01							$ 0.01					$ 0.01
Preferred stock dividend rate per annum (in hundredths)						14.125%							12.00%			12.00%	6.00%	6.00%
Dividends Payable	$ 993,000	$ 1,034,000											$ 81,600,000			$ 80,600,000
Redeemable preferred stock				2,200,000	2,200,000								113,400,000			112,500,000
Preferred stock issued and outstanding (in shares)													3,185,586			3,185,586		2,858,723		433	433	433	677		607	607	607	947
Senior Redeemable Preferred Stock [Abstract]
Redeemable preferred stock liquidation value (in dollar per share)						$ 1,000
Percentage of redeemable preferred stock redeemed (in hundredths)				36.00%	26.70%
Senior redeemable preferred stock maturity date										Aug. 31, 2014
Maximum redemption of redeemable preferred stock									4,000,000
Minimum percentage of discount on redemption of redeemable preferred stock (hundredths)									10.00%
Redemption amount of senior redeemable preferred stock				2,000,000	2,000,000
Gain on redemption of senior preferred stock				200,000	200,000
Percentage of discount on redemption of redeemable preferred stock (in hundredths)				10.00%	10.00%
Common stock held by related parties (in hundredths)																														39.30%
Related party preferred stock held after redemption (in shares)																								359					502
Percentage of redeemable preferred stock held by related party after redemption (in hundredths)										76.40%	6.30%	82.70%
Undeclared unpaid dividends						3,000,000		3,000,000
Accrued dividends reported as interest expenses						36,000	78,000						956,000	956,000
12% Cumulative Exchangeable Redeemable Preferred Stock [Abstract]
Adjusted accrued accretion of public preferred stock															1,500,000
Number of shares declared as dividend (in shares)																	736,863	736,863
Number of annual tranches during the period																			5
Period during which redeemable preferred stock not callable													12 months
Preferred stock dividend rate per annum (in dollars per share)													$ 1.20				$ 0.6	$ 0.6
Preferred stock, liquidation preference (in dollars per share)													$ 10
Dividends on preferred stock	1,000,000	1,000,000
Accrued paid-in kind dividends																			4,000,000
Accrued paid-in cash dividends																			15,100,000
Redemption of public preferred stock (in shares)			410,000
Reduced amount of Paid in kind dividends due to redemption of public preferred stock																			3,500,000
Adjusted amount of accrued cash dividends due to redemption of public preferred stock																			9,900,000
Revised accrued dividends to reflect change from Pik dividends to cash dividends																			$ 13,400,000