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Stock Based Compensation - Additional Information (Detail) - USD ($) | 1 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Jan. 31, 2017 | Jul. 31, 2016 | Jan. 31, 2016 | Jul. 31, 2015 | Jan. 31, 2015 | Jul. 31, 2014 | Jan. 31, 2014 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |  |  |  |  |
Percentage of common stock price paid |  |  |  |  |  |  |  | 85.00% |  |  |
Stock options term |  |  |  |  |  |  |  | 7 years |  |  |
Restricted stock unit awards granted |  |  |  |  |  |  |  | 1,471,000 | 1,681,000 | 1,870,000 |
Weighted average grant date fair value of restricted stock units granted |  |  |  |  |  |  |  | $ 18.68 | $ 17.36 | $ 18.41 |
Stock options granted |  |  |  |  |  |  |  | 130,000 | 132,000 | 89,000 |
Weighted average grant date fair value |  |  |  |  |  |  |  | $ 5.30 | $ 4.43 | $ 5.49 |
Tax benefit from compensation expense |  |  |  |  |  |  |  | $ 8,752,000 | $ 8,528,000 | $ 11,537,000 |
Total unrecognized expense related to non-vested restricted stock unit awards and stock options |  |  |  |  |  |  |  | $ 40,600,000 |  |  |
Unrecognized expense related to non-vested restricted stock unit awards and stock options expected to be recognized over weighted average period, in years |  |  |  |  |  |  |  | 2 years 3 months 18 days |  |  |
Stock based compensation expense |  |  |  |  |  |  | $ 6,600,000 | $ 30,750,000 | $ 30,451,000 | $ 40,307,000 |
Maximum percent of shares allowed to purchase |  |  |  |  |  |  |  | 10.00% |  |  |
Fair market value |  |  |  |  |  |  |  | $ 25,000 |  |  |
Maximum number of shares allowed to purchase |  |  |  |  |  |  |  | 6,000 |  |  |
Common stock issued to employees |  | 500,000 | 500,000 | 500,000 | 500,000 | 500,000 |  |  |  |  |
Value of common stock issued to employees per share |  | $ 16.74 | $ 17.57 | $ 16.40 | $ 16.82 | $ 16.66 |  |  |  |  |
Number of shares available for grant |  |  |  |  |  |  |  | 9,546,000 | 10,914,000 | 12,443,000 | 14,213,000
Stock Options |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |  |  |  |  |
Percentage of common stock price paid |  |  |  |  |  |  |  | 100.00% |  |  |
Period of stock granted to employees and executive officers vest in equal annual installments |  |  |  |  |  |  |  | 4 years |  |  |
Cash received from employees, employee stock options exercises |  |  |  |  |  |  |  | $ 2,900,000 | $ 2,800,000 | $ 6,700,000 |
Tax benefit from compensation expense |  |  |  |  |  |  |  | $ 800,000 | $ 2,100,000 | $ 5,700,000 |
Restricted Stock Units |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |  |  |  |  |
Restricted stock unit awards granted |  |  |  |  |  |  |  | 1,471,000 | 1,681,000 | 1,870,000 |
Restricted Stock Units | Employees |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |  |  |  |  |
Period of stock granted to employees and executive officers vest in equal annual installments |  |  |  |  |  |  |  | 4 years |  |  |
Restricted Stock Units | Director |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |  |  |  |  |
Period of stock granted to employees and executive officers vest in equal annual installments |  |  |  |  |  |  |  | 1 year |  |  |
Percentage of awards vesting on the first anniversary of grant date |  |  |  |  |  |  |  | 100.00% |  |  |
TSR Performance-Based Restricted Stock Units |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |  |  |  |  |
Total shareholder return performance measurement period |  |  |  |  |  |  | 3 years |  |  |  |
Minimum age of retirement to be eligible for PRSUs |  |  |  |  |  |  | 60 years |  |  |  |
Minimum years of service for retirement to be eligible for PRSUs |  |  |  |  |  |  | 10 years |  |  |  |
Restricted stock unit awards granted |  |  |  |  |  |  |  | 100,000 | 200,000 | 100,000 |
Weighted average grant date fair value of restricted stock units granted |  |  |  |  |  |  |  | $ 20.29 | $ 18.21 | $ 22.06 |
Estimated annual dividend amount per share |  |  |  |  |  |  |  | 0.24 | 0.24 | 0.24 |
Stock price |  |  |  |  |  |  |  | $ 19.43 | $ 18.10 | $ 19.16 |
TSR Performance-Based Restricted Stock Units | Share-based Compensation Award, Tranche One |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |  |  |  |  |
Percentage of vesting of target shares upon performance achieved |  |  |  |  |  |  | 200.00% |  |  |  |
TSR Performance-Based Restricted Stock Units | Share-based Compensation Award, Tranche Two |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |  |  |  |  |
Percentage of vesting of target shares upon performance achieved |  |  |  |  |  |  | 0.00% |  |  |  |
Employee Stock Purchase Plan |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |  |  |  |  |
Number of shares available for grant |  |  |  |  |  |  |  | 3,900,000 |  |  |
PBIT Performance-Based Restricted Stock Units |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |  |  |  |  |
Total shareholder return performance measurement period |  |  | 3 years |  |  |  |  |  |  |  |
PBIT Performance-Based Restricted Stock Units | Share-based Compensation Award, Tranche One |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |  |  |  |  |
Percentage of vesting of target shares upon performance achieved |  |  | 200.00% |  |  |  |  |  |  |  |
PBIT Performance-Based Restricted Stock Units | Share-based Compensation Award, Tranche Two |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |  |  |  |  |
Percentage of vesting of target shares upon performance achieved |  |  | 0.00% |  |  |  |  |  |  |  |
Subsequent Event |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |  |  |  |  |
Common stock issued to employees | 400,000 |  |  |  |  |  |  |  |  |  |
Value of common stock issued to employees per share | $ 21.59 |  |  |  |  |  |  |  |  |  |

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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period. + 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 (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target 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)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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