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Capital - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions | 2 Months Ended | 48 Months Ended |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 31, 2018 | Jun. 30, 2016 | Oct. 24, 2018 | Feb. 17, 2016 | Jan. 27, 2015 | Jan. 28, 2014 | Jan. 29, 2013 | Jun. 19, 2012
Disclosure Capital Additional Information [Abstract] |  |  |  |  |  |  |  |
Announcement of common stock repurchase program |  |  | $ 25.0 | $ 25.0 | $ 25.0 | $ 25.0 | $ 25.0 | $ 50.0
Stock repurchased (in shares) | 1,843,373 | 16,665,735 |  |  |  |  |  |
Average price per share | $ 13.58 | $ 7.55 |  |  |  |  |  |

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- Definition Disclosure - Capital - Additional Information [Abstract] + References No definition available. + Details
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- Definition Amount of stock repurchase plan authorized. + References No definition available. + Details
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- Definition Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644 Reference 2: 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 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 4: 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(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Total cost of shares repurchased divided by the total number of shares repurchased. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655 + Details
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