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Stock-Based Compensation Plans (Tables) | 12 Months Ended
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Dec. 31, 2016
Stock Options Plan [Member] |
Assumptions Used to Determine Grant-Date Fair Value of Options | The following weighted average assumptions were used to determine the grant-date fair value of options:
|  | 2016 |  |  | 2015 |  |  | 2014 |
Dividend yield |  |  | 1.38 | % |  |  | 1.03 | % |  |  | 1.34 | %
Expected life |  |  | 5 years |  |  |  | 5 years |  |  |  | 5 years |
Volatility |  |  | 25.11 | % |  |  | 25.5 | % |  |  | 30.7 | %
Risk free interest rate |  |  | 0.91 | % |  |  | 1.05 | % |  |  | 0.97 | %
Summary of Transactions of Company's Stock Option Plans | The following table summarizes the transactions of the Company’s stock option plans for the year ended December 31, 2016:
|  | Number of Options |  |  | Weighted Average Exercise Price |  |  | Weighted Average Grant-Date Fair Value |
Outstanding at December 31, 2015 |  |  | 667,439 |  |  | $ | 19.87 |  |  | $ | 20.19 |
Granted – at discount |  |  | 67,546 |  |  | $ | 0.00 |  |  | $ | 38.13 |
– at market value |  |  | 24,794 |  |  | $ | 44.34 |  |  | $ | 9.17 |
Exercised |  |  | (151,164 | ) |  | $ | 14.38 |  |  | $ | 19.63 |
Forfeited |  |  | (37,621 | ) |  | $ | 14.49 |  |  | $ | 24.83 |
Outstanding at December 31, 2016 |  |  | 570,994 |  |  | $ | 20.38 |  |  | $ | 21.68 |
Stock Equivalent Units [Member] |
Assumptions Used to Determine Fair Value of SEUs | The following assumptions were used to determine the fair value of SEUs at the balance sheet dates:
|  | 2016 |  |  | 2015 |  |  | 2014 |
Dividend yield |  |  | 0.98 | % |  |  | 1.12 | % |  |  | 1.29 | %
Volatility |  |  | 25.2 | % |  |  | 24.6 | % |  |  | 26.0 | %
Risk free interest rate |  |  | 1.47 | % |  |  | 1.31 | % |  |  | 1.10 | %
Summarizes Transactions of SEUs | The following table summarizes the transactions of the Company’s SEUs for the year ended December 31, 2016:
|  | Number of SEUs |  |  | Weighted Average Exercise Price |  |  | Weighted Average Grant-Date Fair Value |
Outstanding at December 31, 2015 |  |  | 279,750 |  |  | $ | 3.79 |  |  | $ | 31.72 |
Granted – at discount |  |  | 70,153 |  |  | $ | 0.00 |  |  | $ | 36.05 |
– at market value |  |  | 7,316 |  |  | $ | 44.18 |  |  | $ | 9.11 |
Exercised |  |  | (66,424 | ) |  | $ | 4.32 |  |  | $ | 27.28 |
Forfeited |  |  | (10,980 | ) |  | $ | 3.61 |  |  | $ | 31.66 |
Outstanding at December 31, 2016 |  |  | 279,815 |  |  | $ | 3.77 |  |  | $ | 33.40 |

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- Definition Tabular disclosure of share-based compensation plans that may be presented in a single table for outstanding, vested and expected to vest, and exercisable awards. The information that may be disclosed in this table may include, but is not limited to, number of shares, weighted average exercise price, weighted average remaining contractual life, and aggregate intrinsic value. + References No definition available. + Details
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- Definition Tabular disclosure of the number and weighted-average exercise prices (or conversion ratios) for share options (or share units) that were outstanding at the beginning and end of the year, vested and expected to vest, exercisable or convertible at the end of the year, and the number of share options or share units that were granted, exercised or converted, forfeited, and expired during the year. + 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) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. + 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 (f)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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