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The cumulative amount of grants made on other than option share-based compensation plans through the balance sheet date.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Number of shares authorized for issuance under share-based payment arrangement.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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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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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Percentage of vesting of award under share-based payment arrangement.

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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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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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Stock-based Compensation - Stock Options (Details) $ / shares in Units, $ in Thousands		12 Months Ended
	May 07, 2014 shares	Dec. 31, 2019 USD ($) item $ / shares shares	Dec. 31, 2018 USD ($) $ / shares shares	Dec. 31, 2017 USD ($) $ / shares shares	Dec. 31, 2016 USD ($) $ / shares shares
Equity Incentive Plan 2010
Stock-based Compensation
Shares included in the authorized shares which was previously reserved for issuance		283,976
Shares
Granted (in shares)	0
Equity Incentive Plan 2014
Stock-based Compensation
Number of shares authorized		5,283,976
Employee and Directors Stock Options
Stock-based Compensation
Term of award		10 years
Vesting period		3 years
Stock-based compensation \| $		$ 0	$ 0	$ 0
Unrecognized compensation cost \| $		$ 0	$ 0	$ 0
Shares
Balance at the beginning of the period (in shares)		2,620,295	2,858,158	3,308,158
Exercised (in shares)		(2,256,142)	(237,863)	(450,000)
Balance at the end of the period (in shares)		364,153	2,620,295	2,858,158	3,308,158
Vested and exercisable at the end of the period (in shares)		364,153
Exercise Price
Balance at the beginning of the period (in dollars per share) \| $ / shares		$ 20.40	$ 20.37	$ 20.40
Exercised (in dollars per share) \| $ / shares		20.00	20.00	20.59
Balance at the end of the period (in dollars per share) \| $ / shares		22.90	$ 20.40	$ 20.37	$ 20.40
Vested and exercisable at the end of the period (in dollars per share) \| $ / shares		$ 22.90
Remaining Contractual Term
Remaining Contractual Term (in years)		9 months	1 year 5 months 26 days	2 years 5 months 26 days	3 years 6 months
Vested and exercisable		9 months
Aggregate Intrinsic Value
Balance at the beginning of the period \| $		$ 25,697	$ 79,230	$ 46,086
Exercised \| $		46,358	5,505	9,397
Balance at the end of the period \| $		8,965	25,697	79,230	$ 46,086
Vested and exercisable at the end of the period \| $		$ 8,965
Restricted Stock Units
Stock-based Compensation
Number of different vesting criteria \| item		4
Stock-based compensation \| $		$ 20,700	$ 17,500	$ 19,800
Unrecognized compensation cost \| $		$ 23,500
Number of shares granted		1,254,904
Restricted Stock Units \| Vesting Tranche One
Stock-based Compensation
Vesting period		3 years
Restricted Stock Units \| Minimum \| Vesting Tranche Two
Stock-based Compensation
Vesting period		1 year
Restricted Stock Units \| Maximum \| Vesting Tranche Two
Stock-based Compensation
Vesting period		2 years
Restricted Stock With Book Value Conditions
Stock-based Compensation
Number of types of book value RSUs \| item		2
Restricted Stock With Book Value Conditions \| Vesting Tranche One
Stock-based Compensation
Vesting period		3 years
Restricted Stock With Book Value Conditions \| Vesting Tranche Two
Stock-based Compensation
Vesting period		3 years
Restricted Stock With Book Value Conditions \| Minimum \| Vesting Tranche Two
Stock-based Compensation
Percentage of shares vested		0.00%
Restricted Stock With Book Value Conditions \| Maximum \| Vesting Tranche Two
Stock-based Compensation
Percentage of shares vested		200.00%
Restricted Stock With Total Shareholder Return Conditions
Stock-based Compensation
Vesting period		3 years
Percentage of shares vested		100.00%
Number of shares granted		429,312
Restricted Stock With Total Shareholder Return Conditions \| Minimum
Stock-based Compensation
Percentage of shares vested		0.00%
Restricted Stock With Total Shareholder Return Conditions \| Maximum
Stock-based Compensation
Percentage of shares vested		200.00%