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Stockholders' Equity - Additional Information (Detail) | 3 Months Ended | 12 Months Ended |  |  |  |
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Dec. 31, 2016 USD ($) $ / shares shares | Sep. 30, 2016 $ / shares | Jun. 30, 2016 $ / shares | Mar. 31, 2016 $ / shares | Dec. 31, 2015 $ / shares shares | Sep. 30, 2015 $ / shares | Jun. 30, 2015 $ / shares | Mar. 31, 2015 $ / shares | Dec. 31, 2014 $ / shares | Sep. 30, 2014 $ / shares | Jun. 30, 2014 $ / shares | Mar. 31, 2014 $ / shares | Dec. 31, 2016 USD ($) $ / shares shares | Dec. 31, 2015 USD ($) $ / shares shares | Dec. 31, 2014 USD ($) Installment $ / shares | Dec. 31, 2012 shares | Oct. 31, 2016 USD ($) | Jul. 31, 2015 USD ($) | Feb. 28, 2015 USD ($) | Dec. 31, 2011 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock, shares authorized | 500,000 |  |  |  | 500,000 |  |  |  |  |  |  |  | 500,000 | 500,000 |  |  |  |  |  |
Preferred stock, par value | $ / shares | $ 0.01 |  |  |  | $ 0.01 |  |  |  |  |  |  |  | $ 0.01 | $ 0.01 |  |  |  |  |  |
Authorized to purchase of common stock under the stock repurchase program | $ | $ 485,000,000 |  |  |  |  |  |  |  |  |  |  |  | $ 485,000,000 |  |  |  | $ 25,000,000 | $ 25,000,000 | $ 25,000,000 |
Cumulative repurchase of common stock | 15,000,000 |  |  |  |  |  |  |  |  |  |  |  | 15,000,000 |  |  |  |  |  |  |
Aggregate cost of repurchase of common stock | $ |  |  |  |  |  |  |  |  |  |  |  |  | $ 424,900,000 |  |  |  |  |  |  |
Dividend declared and paid per share | $ / shares | $ 0.18 | $ 0.18 | $ 0.18 | $ 0.18 | $ 0.17 | $ 0.17 | $ 0.17 | $ 0.17 | $ 0.16 | $ 0.16 | $ 0.16 | $ 0.16 |  |  |  |  |  |  |  |
Dividend declared per share | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.72 | $ 0.68 | $ 0.64 |  |  |  |  |
Aggregate dividend declared for the year | $ |  |  |  |  |  |  |  |  |  |  |  |  | $ 13,000,000 | $ 12,200,000 | $ 12,000,000 |  |  |  |  |
Option Outstanding and vested | 1,540,000 |  |  |  | 2,171,000 |  |  |  |  |  |  |  | 1,540,000 | 2,171,000 |  |  |  |  |  |
Employee Stock Purchase Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Future awards granted or issued under plans | 200,000 |  |  |  |  |  |  |  |  |  |  |  | 200,000 |  |  |  |  |  |  |
Shares authorized | 700,000 |  |  |  |  |  |  |  |  |  |  |  | 700,000 |  |  |  |  |  |  |
Hours of work per week |  |  |  |  |  |  |  |  |  |  |  |  | 20 hours |  |  |  |  |  |  |
Duration of purchase periods under employee stock purchase plan |  |  |  |  |  |  |  |  |  |  |  |  | 6 months |  |  |  |  |  |  |
Holding period of stocks acquired under employee stock purchase plan |  |  |  |  |  |  |  |  |  |  |  |  | 1 year |  |  |  |  |  |  |
Value used to derive maximum number of shares per participant for employee stock purchase | $ |  |  |  |  |  |  |  |  |  |  |  |  | $ 12,500 |  |  |  |  |  |  |
Employee maximum elected percentage reduction of compensation to purchase shares |  |  |  |  |  |  |  |  |  |  |  |  | 10.00% |  |  |  |  |  |  |
Exercise price rate of fair value |  |  |  |  |  |  |  |  |  |  |  |  | 85.00% |  |  |  |  |  |  |
Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average grant date fair value for RSUs granted | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  | $ 37.87 | $ 31.50 | $ 36.67 |  |  |  |  |
Number of shares received per restricted stock unit on lapse of restrictions and vesting condition met |  |  |  |  |  |  |  |  |  |  |  |  | 1 |  |  |  |  |  |  |
Value of RSUs vested and converted to common stock | $ |  |  |  |  |  |  |  |  |  |  |  |  | $ 6,600,000 | $ 4,600,000 | $ 3,500,000 |  |  |  |  |
Stock Options [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Intrinsic value of options exercised | $ |  |  |  |  |  |  |  |  |  |  |  |  | $ 3,700,000 | $ 400,000 | $ 2,300,000 |  |  |  |  |
Equity Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares of common stock options entitlement of non- employee directors | 12,000 |  |  |  |  |  |  |  |  |  |  |  | 12,000 |  |  |  |  |  |  |
Number of installments upon which share based awards vest | Installment |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4 |  |  |  |  |
1996 Equity Plan [Member] | Equity Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Future awards granted or issued under plans | 0 |  |  |  |  |  |  |  |  |  |  |  | 0 |  |  |  |  |  |  |
2006 Director Plan [Member] | Equity Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Future awards granted or issued under plans | 0 |  |  |  |  |  |  |  |  |  |  |  | 0 |  |  |  |  |  |  |
Shares authorized | 450,000,000 |  |  |  |  |  |  |  |  |  |  |  | 450,000,000 |  |  |  |  |  |  |
Shares returned |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 80,000 |  |  |  |
Number of shares of common stock options entitlement of non- employee directors |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6,000,000
Option Outstanding and vested | 200,000 |  |  |  |  |  |  |  |  |  |  |  | 200,000 |  |  |  |  |  |  |
1996 Director [Member] | Equity Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Future awards granted or issued under plans | 0 |  |  |  |  |  |  |  |  |  |  |  | 0 |  |  |  |  |  |  |
Equity Incentive Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity incentive plan extended term |  |  |  |  |  |  |  |  |  |  |  |  | 10 years |  |  |  |  |  |  |
Equity incentive plan expiration |  |  |  |  |  |  |  |  |  |  |  |  | 2026-05 |  |  |  |  |  |  |
Increase in number of shares issuable under plan |  |  |  |  |  |  |  |  |  |  |  |  | 2,000,000 |  |  |  |  |  |  |
Equity Incentive Plan [Member] | Equity Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Future awards granted or issued under plans | 2,700,000 |  |  |  |  |  |  |  |  |  |  |  | 2,700,000 |  |  |  |  |  |  |
Shares authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6,350,000 |  |  |  |
Shares returned |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,500,000 |  |  |  |
Option expiration period |  |  |  |  |  |  |  |  |  |  |  |  | 10 years |  |  |  |  |  |  |
Equity Incentive Plan [Member] | Equity Plan [Member] | Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Options vested period |  |  |  |  |  |  |  |  |  |  |  |  | 4 years |  |  |  |  |  |  |
Prior to 2011 [Member] | Equity Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares of common stock options entitlement of non- employee directors | 12,500 |  |  |  |  |  |  |  |  |  |  |  | 12,500 |  |  |  |  |  |  |

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