v3.10.0.1

Stock-based Compensation (Tables) | 12 Months Ended
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Dec. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract] |
Stock Options, Valuation Assumptions | The weighted-average fair value of options granted and the weighted-average assumptions used in the Black-Scholes-Merton option pricing model for such grants were as follows:
| 2018 | 2017 | 2016
Dividend Yield | 0.3 | % | 0.4 | % | 0.4 | %
Expected Volatility | 34.8 | % | 32.8 | % | 34.2 | %
Risk-free Interest Rate | 2.6 | % | 1.9 | % | 1.3 | %
Expected Term (in years) | 5.3 |  | 5.3 |  | 5.3 |
Weighted-average Fair Value of Stock Options Granted | $ | 16.54 |  | $ | 8.55 |  | $ | 7.10 |
Summary Information about Stock Options Outstanding | The following table summarizes information about stock options outstanding at December 31, 2018:
| Options Outstanding |  | Options Exercisable
Range of Exercise Prices | Number Outstanding December 31, 2018 |  | Weighted Average Remaining Contractual Life (in Years) |  | Weighted Average Exercise Price |  | Number Exercisable December 31, 2018 |  | Weighted Average Exercise Price
$19.92-20.00 | 33,250 |  |  | 1.15 |  | $ | 19.92 |  |  | 33,250 |  |  | $ | 19.92 |
20.01-30.00 | 1,174,285 |  |  | 7.29 |  | 25.50 |  |  | 666,915 |  |  | 25.47 |
30.01-40.00 | 116,496 |  |  | 6.07 |  | 32.13 |  |  | 116,496 |  |  | 32.13 |
40.01-47.26 | 352,650 |  |  | 9.18 |  | 47.26 |  |  | — |  |  | — |
19.92-47.26 | 1,676,681 |  |  | 7.48 |  | 30.42 |  |  | 816,661 |  |  | 26.20 |
Summary of Stock Option Activity | The table below summarizes option activity for the year ended December 31, 2018:
| Options (In Thousands) |  | Weighted Average Exercise Price |  | Weighted Average Remaining Contractual Term (in Years) |  | Aggregate Intrinsic Value (in Thousands) |  | Weighted Average Fair Value
Outstanding at January 1, 2018 | 1,652 |  |  | $ | 25.56 |  |  |  |  |  |  |
Granted | 361 |  |  | 47.26 |  |  |  |  |  |  |
Exercised | (296 | ) |  | 23.90 |  |  |  |  |  |  |
Forfeited/expired | (40 | ) |  | 29.77 |  |  |  |  |  |  |
Outstanding at December 31, 2018 | 1,677 |  |  | 30.42 |  |  | 7.48 |  | $ | 19,496 |  |  | $ | 9.98 |
Expected to Vest | 844 |  |  | 34.20 |  |  | 8.35 |  | 6,624 |  |  | 11.42 |
Exercisable at December 31, 2018 | 817 |  |  | 26.20 |  |  | 6.55 |  | 12,947 |  |  | 8.36 |
Summary of Restricted Stock Activity | The following table summarizes information about restricted stock activity during 2018:
| Restricted Stock (In Thousands) | Weighted Average Fair Value
Non-vested at January 1, 2018 | 947 |  | $ | 27.96 |
Granted | 248 |  | 46.01 |
Vested | (544 | ) | 28.33 |
Forfeited | (62 | ) | 37.46 |
Non-vested at December 31, 2018 | 589 |  | 34.18 |
Summary of Performance Share Units | The following table summarizes information about performance share unit activity during 2018:
| Performance Share Units (In Thousands) |  | Weighted Average Fair Value
Non-vested at January 1, 2018 | 822 |  |  | $ | 26.31 |
Granted | 486 |  |  | 38.51 |
Vested | (458 | ) |  | 26.96 |
Forfeited/unearned | (51 | ) |  | 30.06 |
Non-vested at December 31, 2018 | 799 |  |  | 33.11 |

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- Definition Tabular disclosure of number, weighted-average exercise price or conversion ratio, aggregate intrinsic value, and weighted-average remaining contractual term for outstanding options that are fully vested and expected to vest. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure for stock option plans. Includes, but is not limited to, outstanding awards at beginning and end of year, grants, exercises, forfeitures, and weighted-average grant date fair value. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=109197908&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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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