Allocated Share-based Compensation Expense, Cumulative Adjustment

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- Definition

Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period

+ References

No definition available.

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- Definition

Term Of Warrants Issued

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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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://fasb.org/us-gaap/role/ref/legacyRef
-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=109197908&loc=d3e5070-113901

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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://fasb.org/us-gaap/role/ref/legacyRef
-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=109197908&loc=d3e5070-113901

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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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.

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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)(2)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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Stock-Based Compensation - Stock Options (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Tax benefit			$ 8,900	$ 9,000	$ 15,900
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in dollars per share)			$ 15.41	$ 19.04	$ 14.87
Intrinsic value			$ 15,200	$ 16,300	$ 63,900
Tax benefit			$ 3,000	$ 5,800	$ 23,700
Warrants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of warrants issued			12 years
Warrants \| Class A Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrants outstanding			$ 1,920
Exercise price (in dollars per share)			$ 4.66
Warrants \| Class C Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrants outstanding			$ 1,930
Exercise price (in dollars per share)			$ 4.56
Certain Executives and Key Employees \| 2005 Plan \| Performance Based Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)			300	500
Certain Executives and Key Employees \| 2005 Plan \| Performance Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)			800	1,900	2,500
Shares granted (in dollars per share)			$ 15.60	$ 18.76	$ 35.71
Certain Executives and Key Employees \| 2005 Plan \| Performance-Based Awards Granted in 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated compensation expense, cumulative adjustment	$ 4,200
Certain Executives and Key Employees \| 2005 Plan \| Performance-Based Awards Granted in 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated compensation expense, cumulative adjustment		$ 3,600
Certain Executives and Key Employees \| 2005 Plan \| Performance-Based Awards Granted in 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated compensation expense, cumulative adjustment		$ 8,000