Shareholders' Equity - Additional Information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014		Jun. 30, 2013		Jun. 10, 2014	Dec. 31, 2013
Class of Stock [Line Items]
Preferred Stock, Shares Issued								11,500
Stockholders' Equity, Other			$ 1,059	[1]	$ (45,542)	[1]
Preferred Stock Conversions, Inducements	3,368	0	3,368		0
Preferred stock dividends (in dollars per share)			$ 300
Preferred stock dividend rate			6.00%
Proceeds from Issuance of Convertible Preferred Stock	314,000		313,646		0
Other Comprehensive loss, pension and postretirements obligations, before tax			75		58
Change in pension and postretirement obligations, net of tax	13	10	26		20
Depositary Shares Issued During Period, New Issues	3,250,000
Depositary Share Interest in a Share of 6.00% Convertible Perpetual Preferred Stock, Series B	0
Preferred Stock, Liquidation Preference Per Share	$ 10,000		$ 10,000
Conversion Price per Share	$ 18.34		$ 18.34
Convertible Preferred Stock, Shares Issued upon Conversion	545.17
Premium, Conversion Price to Common Share Closing Price Prior to Series B Preferred Stock Offering							30.00%
Common Share Price, Last Reported Prior to Series B Preferred Stock Offering							$ 14.11
Premium, Conversion Ratio into Common Stock if Closing Sale Price Exceed Prior Period Conversion Price	130.00%		130.00%
Depositary Shares [Member]
Class of Stock [Line Items]
Conversion of Stock, Shares Converted	262,012
Series A Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Shares Issued	8,880		8,880
Preferred Stock Conversions, Inducements			$ 3,400
Conversion of Stock, Shares Converted for Inducement Consideration	2,593
Series B Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Shares Issued	32,500		32,500
Preferred stock dividend rate			6.00%
Stock Issued During Period, Shares, New Issues	32,500
Convertible Preferred Stock
Class of Stock [Line Items]
Conversion of Stock, Shares Converted	2,620

[1] Includes equity-classified share-based compensation of $1,651 and $3,771 for the six months ended June 30, 2014 and 2013.