Stock Incentive Plans - Summary of Non-vested Restricted Stock Units ("RSUs") (Details) - RSUs issued and unvested - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Shares Underlying RSUs
Beginning balance (in shares)	547,891
Granted (in shares)	629,901
Vested (in shares)	(180,842)
Forfeited (in shares)	(110,920)
Ending balance (in shares)	886,030	547,891
Weighted Average Grant Date Fair Value
Beginning balance (in USD per share)	$ 56.62
Granted (in USD per share)	87.72
Vested and released (in USD per share)	52.52
Forfeited (in USD per share)	69.77
Ending balance (in USD per share)	$ 77.92	$ 56.62
Weighted Remaining Vesting Period (in years)
ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingWeightedAverageRemainingContractualTerms	1 year 4 months 20 days	2 years 5 months 12 days
ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingWeightedAverageRemainingContractualTerms	1 year 4 months 20 days	2 years 5 months 12 days
Aggregate Intrinsic Value (in thousands)
Beginning balance	$ 38,067
Ending balance	$ 60,330	$ 38,067

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Shares Underlying RSUs

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Weighted Average Grant Date Fair Value

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Weighted Remaining Vesting Period (in years)

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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).

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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).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Intrinsic value of outstanding award under share-based payment arrangement. Excludes share and unit options.

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