Preferred Stock - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Nov. 06, 2015
Class of Stock [Line Items]
Discount on preferred stock amortized period	5 years
Fixed Rate Cumulative Perpetual Preferred Stock, Series A [Member]
Class of Stock [Line Items]
Preferred stock, shares outstanding		13,900
Preferred Stock, redemption amount		$ 13,900
Preferred stock, shares issued	13,900
Par value	$ 1.25
Preferred stock, liquidation preference	1,000
Fixed Rate Cumulative Perpetual Preferred Stock, Series B [Member]
Class of Stock [Line Items]
Preferred stock, shares outstanding		695
Preferred Stock, redemption amount		$ 695
Par value	1.25
Preferred stock, liquidation preference	$ 1,000
Number of shares	695
Cumulative dividends of warrant preferred stock	9.00%
Purchase Agreement [Member]
Class of Stock [Line Items]
Cumulative dividends percentage until May 14, 2014	5.00%
Cumulative dividend thereafter	9.00%