Employee Compensation Plans - Stock Appreciation Rights (Details) - Stock Appreciation Rights (SARs) [Member] - $ / shares			12 Months Ended
Jan. 11, 2019	Dec. 31, 2018	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement By Cash Payment Award Stock Appreciation Rights Outstanding Number		2,125,660	2,125,660
Share Based Compensation Arrangement By Cash Payment Award Stock Appreciation Rights unvested amount		2,100,000	2,100,000
Total Number of OARs outstanding		0	0
Total weighted average strike price		$ 0	$ 0
Total weighted average remaining contractual life			2 years 1 month
Total weighted average fair value per share		$ 0	$ 0
Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number Of Stock Appreciation Rights Granted	560,156
January Five Two Thousand Eighteen [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement By Cash Payment Award Stock Appreciation Rights Outstanding Number		482,720	482,720
Strike price		$ 0	$ 0
Remaining contractual life		4 years
Fair value per share		$ 0	$ 0
January Six Two Thousand Seventeen [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement By Cash Payment Award Stock Appreciation Rights Outstanding Number		409,660	409,660
Strike price		$ 0	$ 0
Remaining contractual life		3 years
Fair value per share		$ 8.3245	$ 8.3245
January Six Two Thousand Sixteen
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement By Cash Payment Award Stock Appreciation Rights Outstanding Number		425,900	425,900
Strike price		$ 0	$ 0
Remaining contractual life		2 years
Fair value per share		$ 0	$ 0
January Nine Two Thousand Fifteen [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement By Cash Payment Award Stock Appreciation Rights Outstanding Number		428,920	428,920
Strike price		$ 0	$ 0
Remaining contractual life		1 year
Fair value per share		$ 0	$ 0
January Fourteen Two Thousand Fourteen [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement By Cash Payment Award Stock Appreciation Rights Outstanding Number		378,460	378,460
Strike price		$ 0	$ 0
Remaining contractual life		13 days
Fair value per share		$ 0	$ 0

Number of stock appreciation rights granted.

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- Definition

The fair value per share of each stock appreciation rights award outstanding by grant date as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

The number of each stock appreciation rights award outstanding as of the balance sheet date.

+ References

No definition available.

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- Definition

The remaining contractual term of the stock appreciation rights outstanding by grant date as of the balance sheet date.

+ References

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- Definition

The strike price of each stock appreciation rights award outstanding.

+ References

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- Definition

The weighted average fair value per share of the total stock appreciation rights outstanding as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

The weighted average remaining contractual term of the total stock appreciation rights outstanding as of the balance sheet date.

+ References

No definition available.

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- Definition

The weighted average strike price of the total stock appreciation rights outstanding as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Share Based Compensation Arrangement By Cash Payment Award Stock Appreciation Rights unvested amount

+ References

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- Definition

Share Based Compensation Arrangement By Cash Payment Award Stock Appreciation Rights vested amount

+ References

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+ Details

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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

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