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Shareholders' Equity - Summary of Stock Option Activity (Detail) - $ / shares | 12 Months Ended
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Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Statement of Stockholders' Equity [Abstract] |  |  |  |
Outstanding shares, beginning balance | 4,300 | 8,290,251 | 16,690,472 |
Options forfeited, Lower Range, Price Per Share | $ 16.73 | $ 16.73 | $ 16.73 |
Options forfeited, shares | (4,300) | (8,285,951) | (8,400,221) |
Options forfeited, Upper Range, Price Per Share | $ 16.73 | $ 27.21 | $ 27.21 |
Outstanding shares, ending balance | 0 | 4,300 | 8,290,251 | 16,690,472
Stock option plans, Lower price range | $ 0 | $ 16.73 | $ 16.73 | $ 16.73
Outstanding, Weighted Average Price Per Share, beginning | 16.73 | 22.64 | 21.00 |
Stock option plans, Upper price range | 0 | 16.73 | 27.21 | 27.21
Options forfeited, Weighted Average Price Per Share | 16.73 | 22.65 | 19.39 |
Outstanding, Weighted Average Price Per Share, ending | $ 0 | $ 16.73 | $ 22.64 | $ 21.00

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- Definition The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv)(3) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Number of options outstanding, including both vested and non-vested options. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated. + References No definition available. + Details
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- Definition The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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