Earnings Per Share - Additional Information (Detail) shares in Millions		3 Months Ended	9 Months Ended
May 09, 2018 $ / shares	Sep. 30, 2018 $ / shares shares	Sep. 30, 2017 shares	Sep. 30, 2018 $ / shares shares	Sep. 30, 2017 shares	Dec. 31, 2017 $ / shares
Earnings Per Share [Abstract]
Reverse stock split	three-to-one
Reverse stock split, conversion ratio	3
Common stock, par value \| $ / shares	$ 1.00	$ 1.00		$ 1.00		$ 1.00
Antidilutive securities excluded from earnings per share computation, shares \| shares		0.5	0.5	0.5	0.5

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
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Face amount or stated value per share of common stock.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 4
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Description of the reverse stock split arrangement. Also provide the retroactive effect given by the reverse split that occurs after the balance sheet date but before the release of financial statements.

+ References

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