Basis of Presentation - Additional Information (Detail) - Common Stock [Member] shares in Billions	Oct. 05, 2016 shares	Oct. 04, 2016 shares
Basis Of Presentation [Line Items]
Reverse stock split ratio	0.33
Common stock share outstanding	0.4	1.3

Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB TOPIC 4.C)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Stock Split
-URI http://asc.fasb.org/extlink&oid=6525746

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Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration