Redeemable Preferred Stock (Details)		1 Months Ended	3 Months Ended		9 Months Ended	12 Months Ended	30 Months Ended
	Nov. 30, 1998 shares	Dec. 31, 2009 Tranche	Sep. 30, 2016 USD ($) $ / shares shares	Jun. 30, 2006 USD ($)	Sep. 30, 2016 USD ($) $ / shares shares	Dec. 31, 1991 $ / shares shares	Jun. 30, 1995 USD ($)	Dec. 31, 2015 USD ($)	Mar. 31, 2015	Dec. 31, 1990 shares
Senior Redeemable Preferred Stock [Abstract]
Redeemable preferred stock liquidation value (in dollar per share) | $ / shares			$ 1,000		$ 1,000
12% Cumulative Exchangeable Redeemable Preferred Stock [Abstract]
Number of annual tranches during the period | Tranche		5
Accrued paid-in kind dividends | $							$ 4,000,000
Accrued paid-in cash dividends | $							15,100,000
Redemption of public preferred stock (in shares) | 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
Senior Redeemable Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock dividend rate per annum					14.125%
Senior Redeemable Preferred Stock [Abstract]
Undeclared unpaid dividends | $			$ 1,600,000		$ 1,600,000
Accrued dividends reported as interest expenses | $			$ 17,000		$ 50,000
Senior Redeemable Preferred Stock [Member] | Toxford [Member]
Senior Redeemable Preferred Stock [Abstract]
Senior redeemable preferred stock maturity date					May 31, 2018
Percentage of redeemable preferred stock held by related party after redemption			76.40%		76.40%
Senior Redeemable Preferred Stock [Member] | Porter [Member]
Senior Redeemable Preferred Stock [Abstract]
Percentage of redeemable preferred stock held by related party after redemption			6.30%		6.30%
Senior Redeemable Preferred Stock [Member] | Porter And Toxford [Member]
Senior Redeemable Preferred Stock [Abstract]
Percentage of redeemable preferred stock held by related party after redemption			82.70%		82.70%
Public Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock authorized (in shares) | shares			6,000,000		6,000,000
Preferred stock par value (in dollar per share) | $ / shares			$ 0.01		$ 0.01
Preferred stock dividend rate per annum					12.00%	6.00%
Dividends Payable | $			$ 94,000,000		$ 94,000,000			$ 92,100,000
Carrying value of redeemable preferred stock | $			$ 126,800,000		$ 126,800,000			$ 123,900,000
Preferred stock issued and outstanding (in shares) | shares			3,185,586		3,185,586
Preferred stock issued (in shares) | shares										2,858,723
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) | shares						736,863
Period during which redeemable preferred stock not callable					12 months
Preferred stock dividend rate per annum (in dollars per share) | $ / shares					$ 1.20	$ 0.60
Preferred stock, liquidation preference (in dollars per share) | $ / shares			$ 10		$ 10
Dividends on preferred stock | $			$ 1,000,000		$ 2,900,000
Series A-1 Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock authorized (in shares) | shares			1,250		1,250
Preferred stock par value (in dollar per share) | $ / shares			$ 0.01		$ 0.01
Senior Redeemable Preferred Stock [Abstract]
Related party preferred stock held after redemption (in shares) | shares			163		163
Series A-2 Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock authorized (in shares) | shares			1,750		1,750
Preferred stock issued and outstanding (in shares) | shares			276		276
Senior Redeemable Preferred Stock [Abstract]
Related party preferred stock held after redemption (in shares) | shares			228		228
Series A-2 Preferred Stock [Member] | Senior Redeemable Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock issued and outstanding (in shares) | shares			197		197
Class A Common Stock [Member] | Porter And Toxford [Member]
Senior Redeemable Preferred Stock [Abstract]
Common stock held by related parties			39.30%		39.30%
Percentage of redeemable preferred stock held by related party after redemption									39.30%