Series D Preferred Shares - Additional Information (Detail)			12 Months Ended
	Dec. 07, 2016 USD ($) shares	Oct. 01, 2012 USD ($) $ / shares shares	Dec. 31, 2016 USD ($) $ / shares shares	Dec. 31, 2015 USD ($) shares	Sep. 30, 2015 USD ($) Covenant
Temporary Equity [Line Items]
Aggregate purchase price under Securities Purchase Agreement | $			$ 100,000,000
Stock Appreciation Rights | shares		6,735,667
Percentage of aggregate amount of common shares issuable upon exercise of warrants			5.00%
Repurchase shares price | $			$ 11,600,000
Warrants exercisable for common shares | shares			9,931,000
Warrants and investor SARs | $			$ 30,400,000	$ 26,200,000
Adjusted
Temporary Equity [Line Items]
Stock Appreciation Rights | shares			7,485,045
Warrants exercisable for common shares | shares			11,035,875
ARS VI
Temporary Equity [Line Items]
Aggregate purchase price under Securities Purchase Agreement | $		$ 100,000,000
Preferred Series D
Temporary Equity [Line Items]
Cumulative redeemable preferred shares, shares issued | shares	3,536,000
Preferred shares with warrants | shares		9,931,000
Maturity of unsecured promissory note			180 days
Percentage of outstanding Series D preferred shares or warrants			10.00%
Shares repurchase and cancel, shares | shares	464,000
Repurchase shares price | $	$ 11,600,000
Cumulative redeemable preferred shares, shares outstanding | shares	3,536,000
Preferred Shares, Dividend Rate			7.50%
Preferred Shares, Dividend Rate increase per each anniversary			0.50%
Liquidation preference per share to October 1, 2017			$ 26.25
Liquidation preference per share after five years			$ 25.00
Warrants Exercise Price		$ 6.00
Warrants exercisable date			Oct. 01, 2027
Stock Appreciation Rights Exercise Price		$ 6.00
Preferred Series D | Maximum
Temporary Equity [Line Items]
Preferred stock redemption amount | $			$ 44,200,000
Preferred Series D | October 1, 2015
Temporary Equity [Line Items]
Preferred Shares, Dividend Rate			8.50%
Preferred Series D | Prior To October 1, 2017
Temporary Equity [Line Items]
Redemption price			$ 26.25
Preferred Series D | After October 1, 2017
Temporary Equity [Line Items]
Redemption price			25.00
Preferred Series D | October 1, 2019
Temporary Equity [Line Items]
Redemption price			25.00
Put price per warrant			1.99
Put price per SARs			1.99
Preferred Series D | Prior to October 1, 2018
Temporary Equity [Line Items]
Put price per warrant			1.23
Put price per SARs			1.23
Preferred Series D | October 1, 2018
Temporary Equity [Line Items]
Put price per warrant			1.60
Put price per SARs			1.60
Preferred Series D | October 1, 2014
Temporary Equity [Line Items]
Stock appreciation rights call price			5.00
Preferred Series D | Adjusted
Temporary Equity [Line Items]
Warrants Exercise Price			5.39
Stock Appreciation Rights Exercise Price			$ 5.39
Preferred Series D | ARS VI
Temporary Equity [Line Items]
Cumulative redeemable preferred shares, shares issued | shares		4,000,000
Cumulative Redeemable Preferred Shares, par value		$ 0.01
Number of covenants | Covenant					2
Consideration paid under Securities Purchase Agreement | $					$ 450,000
Series D Cumulative Redeemable Preferred Stock
Temporary Equity [Line Items]
Cumulative redeemable preferred shares, shares issued | shares			3,536,000	4,000,000
Cumulative redeemable preferred shares, shares outstanding | shares			3,536,000	4,000,000