v3.7.0.1

Accounting Policies - Additional Information (Detail) | Nov. 18, 2014 shares | Aug. 04, 2014 shares | Dec. 31, 2016 shares | Dec. 31, 2015 shares
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Accounting Policies [Abstract] |  |  |  |
Common Stock, shares issued |  | 13,400,000 |  |
Stock Split ratio | 5 |  |  |
Common stock, shares outstanding | 67,100,000 |  | 67,600,000 | 67,900,000
Common stock, shares authorized | 400,000,000 |  | 400,000,000 | 400,000,000

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