| **Earnings per Share - Common Stock Equivalents Not Included in Computation of Diluted Earnings Per Share (Detail) - $ / shares** | 12 Months Ended |
|-----------------------------------------------------------------------------------------------------------------------------------|-----------------|
||
| **Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]**                                          |            |   |   |
| Common stock, par value (in dollars per share)                                                                                    | $ 1             | $ 1 |   |
| Restricted Stock [Member]                                                                                                         |            |   |   |
| **Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]**                                          |            |   |   |
| Antidilutive securities excluded from computation of earnings per share, shares                                                   | 71,560          | 18,173 | 67,920 |
| Minimum [Member] | Restricted Stock [Member]                                                                                      |            |   |   |
| **Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]**                                          |            |   |   |
| Common stock, par value (in dollars per share)                                                                                    | $ 8.84          | $ 8.55 | $ 8.38 |
| Maximum [Member] | Restricted Stock [Member]                                                                                      |            |   |   |
| **Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]**                                          |            |   |   |
| Common stock, par value (in dollars per share)                                                                                    | $ 14.49         | $ 13.96 | $ 13.96 |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
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.
+ References
Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Face amount or stated value per share of common stock.
+ References
Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682
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| X                                                                                                                                                                                                                         |
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| X                                                                                                                       |
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| X                                                                                                                       |
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