Equity-based Compensation - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock granted	645,346	0
Number of unit will vest	44,501	0
Equity-based compensation expense	$ 0.9	$ 0.4
Remaining expense related to unvested restricted stock units	$ 15.1
Restricted Stock Units \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expense recognition period	24 months
Restricted Stock Units \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expense recognition period	30 months
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period	3 years
Expense recognition period	33 months
Percentage of premium on common stock value, options granted	15.00%
Option expiration period	7 years
Expense related to nonvested stock option grants	$ 3.5
Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares available for grant	7,500,000
Shares of common stock remain available for future grants	6,406,988
Plan \| Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock granted	645,346
Plan \| Restricted Stock Units \| Vesting Quarterly
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of unit will vest	415,940
Plan \| Restricted Stock Units \| Half of Units Granted
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period	3 years
Plan \| Restricted Stock Units \| Cliff-Vest
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of unit will vest	57,521
Plan \| Restricted Stock Units \| Remaining Half of Units Granted
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period	3 years
Award vesting rights	The remaining half of the restricted stock units vest equally in the first quarter of each of the next three years
Plan \| Restricted Stock Units \| Minimum \| Half of Units Granted
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting rights, percentage	25.00%
Plan \| Restricted Stock Units \| Maximum \| Half of Units Granted
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting rights, percentage	200.00%

Share based compensation arrangement by share based payment award excercise price premium percentage.

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
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Unrecognized cost of unvested share-based compensation awards.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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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.

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Publisher FASB
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Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date.

+ References

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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

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

Percentage of vesting of share-based compensation awards.

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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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