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Employee Benefit Plans - Additional Information (Detail) | 3 Months Ended | 12 Months Ended
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Jun. 30, 2017 shares | Jun. 30, 2015 shares | Jun. 30, 2012 shares | Dec. 31, 2017 USD ($) Plans Members Employer shares | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Number of active stock compensation plans | Plans |  |  |  | 3 |  |
Restricted stock shares | shares |  |  |  | 600,000 |  |
Number of employers obligated to make contribution under multiemployer plan | Employer |  |  |  | 201 |  |
Pension Protection |  |  |  | 2006 | 2006 | 2006
Number of employee increase / (decrease) under multiemployer benefit percentage |  |  |  | 0.50% | 2.60% |
Total contributions of multi employer Plan |  |  |  |  | 5.00% | 5.00%
Plans In Red Zone [Member] |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Multiemployer Benefit AI Pension Plan |  |  |  | Less than 65 percent |  |
Plans In Yellow Zone [Member] |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Multiemployer Benefit AI Pension Plan |  |  |  | Between 65 and less than 80 percent |  |
Plans In Green Zone [Member] |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Multiemployer Benefit AI Pension Plan |  |  |  | At least 80 percent |  |
Supplemental Employee Retirement Plans, Defined Benefit [Member] |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Members of senior management | Members |  |  |  | 12 |  |
Stock Option [Member] | Selling, General and Administrative Expenses [Member] |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Compensation expense | $ |  |  |  | $ 0 | $ 0 | $ 0
Restricted Stock Units and Restricted Stock Awards [Member] |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Tax benefits recognized related to compensation expense | $ |  |  |  | 4,200,000 | 4,200,000 | 3,700,000
Restricted Stock Units and Restricted Stock Awards [Member] | Selling, General and Administrative Expenses [Member] |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Compensation expense | $ |  |  |  | 11,100,000 | 11,200,000 | 9,800,000
Non-vested Restricted Stock Units and Restricted Stock Awards [Member] |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Compensation expense not yet recognized | $ |  |  |  | $ 34,200,000 |  |
Total compensation cost related to non-vested options expected to be recognized over weighted average period |  |  |  | 7 years 6 months |  |
401(k) plan [Member] |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Employer contribution | $ |  |  |  | $ 8,000,000 | $ 8,000,000 | $ 7,700,000
2012 Formula Plan [Member] | Restricted Stock [Member] | Director [Member] |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Restricted stock shares | shares |  |  |  | 40,000 |  |
2012 Formula Plan [Member] | Common Class A [Member] |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Number of shares authorized | shares | 500,000 |  | 300,000 |  |  |
2012 Plan [Member] | Restricted Stock Units [Member] |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Stock award vesting period |  |  |  | 3 years |  |
2012 Plan [Member] | Restricted Stock Units [Member] | Executive Officer and Other Key Associates [Member] |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Restricted stock shares | shares |  |  |  | 560,000 |  |
2012 Plan [Member] | Common Class A [Member] |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Number of shares authorized | shares |  | 4,000,000 | 2,000,000 |  |  |
2004 Stock Incentive Plan and 2012 Formula Plan [Member] | Common Class A [Member] | Stock Option [Member] |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Stock option expiration period |  |  |  | 10 years |  |
2004 Stock Incentive Plan and 2012 Formula Plan [Member] | Common Class A [Member] | Stock Option [Member] | Minimum [Member] |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Stock award vesting period |  |  |  | 6 months |  |
2004 Stock Incentive Plan and 2012 Formula Plan [Member] | Common Class A [Member] | Stock Option [Member] | Maximum [Member] |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Stock award vesting period |  |  |  | 3 years |  |
2004 Stock Incentive Plan and 2012 Formula Plan [Member] | Common Class A [Member] | Non-vested Restricted Stock Awards and Restricted Stock Units [Member] | Minimum [Member] |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Stock award vesting period |  |  |  | 1 year |  |
2004 Stock Incentive Plan and 2012 Formula Plan [Member] | Common Class A [Member] | Non-vested Restricted Stock Awards and Restricted Stock Units [Member] | Maximum [Member] |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Stock award vesting period |  |  |  | 3 years |  |

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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=96867065&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=96867065&loc=d3e5070-113901 + Details
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- Definition Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + 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 (i) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Increase (decrease) in the percentage of the entity's employees covered by the pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 6 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450673-114947 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 11 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450702-114947 + Details
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- Definition Indicate whether the multiemployer plan is less than 65 percent funded, between 65 and less than 80 percent funded, or at least 80 percent funded. The acceptable values are: (1) "less than 65 percent", (2) "between 65 and less than 80 percent", (3) "at least 80 percent", and (4) "NA". A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 + Details
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- Definition The number of grants made 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=96867065&loc=d3e5070-113901 + Details
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- Definition Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + 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 (a)(2) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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