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Capital - Additional Information (Detail) $ / shares in Units, $ in Thousands | 12 Months Ended | 48 Months Ended |  |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 31, 2016 program $ / shares shares | Jun. 30, 2016 $ / shares shares | Dec. 02, 2016 USD ($) branch | Oct. 03, 2016 USD ($) branch | Feb. 17, 2016 shares | Jan. 27, 2015 shares | Jan. 28, 2014 shares | Jan. 29, 2013 shares | Jun. 19, 2012 USD ($)
Announcement of common stock repurchase program |  |  |  |  |  |  |  |  | $ 50,000
Number of shares authorized to be repurchased | shares |  |  |  |  | 25,000,000.0 | 25,000,000.0 | 25,000,000.0 | 25,000,000.0 |
Number of repurchase programs | program | 4 |  |  |  |  |  |  |  |
Stock repurchased (in shares) | shares | 45,612 | 16,665,735 |  |  |  |  |  |  |
Average price per share | $ / shares | $ 8.46 | $ 7.55 |  |  |  |  |  |  |
FirstMerit Bank, NA, Branch Acquisition [Member] |  |  |  |  |  |  |  |  |
Business Combination, Acquired Receivables, Gross Contractual Amount |  |  | $ 105,627 |  |  |  |  |  |
Number of Stores | branch |  |  | 13 |  |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets |  |  | $ 121,197 |  |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deposits |  |  | $ 619,729 |  |  |  |  |  |
DCB Financial Corp [Member] |  |  |  |  |  |  |  |  |
Business Combination, Acquired Receivables, Gross Contractual Amount |  |  |  | $ 388,000 |  |  |  |  |
Number of Stores | branch |  |  |  | 9 |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets |  |  |  | $ 550,000 |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deposits |  |  |  | $ 477,000 |  |  |  |  |

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- Definition Stock Repurchase Program, Number of Repurchase Programs + References No definition available. + Details
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- Definition For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the gross contractual amounts receivable, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=73530397&loc=d3e4845-128472 + Details
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- Definition Amount of assets acquired at the acquisition date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=73530397&loc=d3e4845-128472 + Details
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- Definition Represents the number of stores. + 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 The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan. + 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://www.xbrl.org/2003/role/presentationRef -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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -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 3: http://www.xbrl.org/2003/role/presentationRef -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 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 + Details
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- Definition Total cost of shares repurchased divided by the total number of shares repurchased. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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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