Stockholder's Equity - Cumulative Convertible Preferred Stock (Detail) - shares shares in Thousands	Dec. 31, 2015	Dec. 31, 2014
Convertible Preferred Stock [Line Items]
Shares issued and outstanding	10	12
Common shares resulting if converted	25	35
Series A [Member]
Convertible Preferred Stock [Line Items]
Shares issued and outstanding	10	10
Conversion factor	2.50%	2.50%
Common shares resulting if converted	25	25
Series M [Member]
Convertible Preferred Stock [Line Items]
Shares issued and outstanding		2
Conversion factor		5.00%
Common shares resulting if converted		10

Number of shares issued for each share of convertible preferred stock that is converted.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29
-Article 5

Name:	us-gaap_ConvertiblePreferredStockSharesIssuedUponConversion
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant