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Deferred Compensation - Additional information (Detail) - USD ($) shares in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2017 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2016
Investments And Employee Deferred Compensation Plan [Line Items] |  |  |  |
Deferred Equity Participation Plan, distributions to key executives, age |  |  |  | Age 62 (or the one-year anniversary of the date of the grant for participants over the age of 61 as of the grant date) or upon or after their actual retirement.
Deferred Equity Participation Sub-plans, distributions to key executives, age |  |  |  | Age 65
Deferred Equity Participation Sub-plans, distributions requisite service description |  |  |  | We made awards under sub-plans of the DEPP for certain production staff, which generally provide for vesting and/or distributions no sooner than five years from the date of awards, although certain awards vest and/or distribute after the earlier of fifteen years or the participant reaching age 65.
Deferred Equity Participation Plan (DEPP) [Member] |  |  |  |
Investments And Employee Deferred Compensation Plan [Line Items] |  |  |  |
Awards approved by committee, value | $ 14,000,000 |  | $ 10,100,000 |
Charge to compensation expenses related to awards | 1,800,000 |  | 1,400,000 |
Cash and equity awards with aggregate fair value vested and distributed to participants | 0 |  | 4,900,000 |
Unearned deferred compensation, value | $ 66,400,000 |  |  | $ 46,800,000
Unearned deferred compensation, shares | 2.7 |  |  | 2.4
Total intrinsic value of unvested equity based awards | $ 153,700,000 |  |  | $ 125,500,000
Deferred Cash Participation Plan (DCPP) [Member] |  |  |  |
Investments And Employee Deferred Compensation Plan [Line Items] |  |  |  |
Awards approved by committee, value | 5,100,000 |  | 3,100,000 |
Charge to compensation expenses related to awards | 400,000 |  | 300,000 |
Cash and equity awards with aggregate fair value vested and distributed to participants | 0 |  | $ 0 |
Deferred Equity Participation Plan Sub Plans [Member] |  |  |  |
Investments And Employee Deferred Compensation Plan [Line Items] |  |  |  |
Awards approved by committee, value |  | $ 13,600,000 |  |
Charge to compensation expenses related to awards | 400,000 |  |  |
Cash and equity awards with aggregate fair value vested and distributed to participants | $ 0 |  |  |

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- Definition Deferred Equity Participation Plan, Distributions to Key Executives, Age + References No definition available. + Details
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- Definition Deferred equity participation sub plan distributions requisite service description. + References No definition available. + Details
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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 Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares. + 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 (d)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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