Cash bonus, Percent

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Restricted stock shares and restricted stock units included in SLO Award target.

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Share based compensation arrangement by share based payment award cumulative stockholder return rate.

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Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Performance Units

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Performance Units Earn Out Percentage

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- Definition

Target level for the determination of performance goals and measures.

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- Definition

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

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- Definition

Amount of noncash expense for share-based payment arrangement.

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- Definition

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

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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).

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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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- 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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Number of shares issued under share-based payment arrangement.

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Price of a single share of a number of saleable stocks of a company.

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- Definition

Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

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Number of shares of stock issued during the period pursuant to acquisitions.

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Stockholders' Equity (Deficit) - Chief Operating Officer (COO) and Chief Executive Officer-Designate 2017 New Hire Equity Awards and 2020 Award Modifications (Details) - USD ($)				1 Months Ended	12 Months Ended
	Dec. 10, 2020	Sep. 26, 2018	Sep. 18, 2017	Feb. 29, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Target level for the determination of performance goals and measures					100.00%
Performance units paid out (in units)				0
Expense related to the SLO program					$ 41,700,000	$ 32,900,000	$ 29,200,000
Share-based incentive compensation					$ 42,300,000	$ 34,400,000	$ 29,900,000
Performance-vesting New Hire Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
granted (in dollars per share)			$ 12.67
2017- 2019 PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance units paid out percentage				90.30%
Performance units paid out (in units)				216,581
Shares withheld for tax (in shares)				82,829
SLO Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units granted (in shares)					8,471	6,321	109,841
Increments of cash bonus, percent					25.00%
Restricted stock shares and restricted stock units included in SLO Award target (in shares)					69,950
Expense related to the SLO program					$ 2,200,000	$ 3,200,000	$ 1,600,000
Share-based incentive compensation					$ 2,200,000	$ 3,200,000	$ 1,600,000
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued (in shares)					73,731
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued as part of acquisition (in shares)		20,000			0	0	20,000
Forfeited (in shares)					15,271	110,984	86,518
Performance Share Unit Awards For Acquisitions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units granted (in shares)								30,506
Performance units paid out percentage					0.00%
Forfeited (in shares)					0	7,130	5,177
Share-based incentive compensation					$ 0	$ (400,000)	$ 300,000
Chief Operating Officer and CEO-Designate \| Time Vesting New Hire Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units granted (in shares)			30,000
granted (in dollars per share)			$ 42.89
Chief Operating Officer and CEO-Designate \| Performance-vesting New Hire Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units granted (in shares)	35,000		70,000
granted (in dollars per share)	$ 45.40
Target level for the determination of performance goals and measures			100.00%
Chief Operating Officer and CEO-Designate \| Time Vesting New Hire Award, Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units granted (in shares)	35,000
Chief Operating Officer and CEO-Designate \| Tranche One \| Performance-vesting New Hire Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cumulative stockholder return rate			33.00%
Chief Operating Officer and CEO-Designate \| Minimum \| Tranche One \| Performance-vesting New Hire Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share price (in dollars per share)			$ 60.00
Chief Operating Officer and CEO-Designate \| Minimum \| Tranche Two \| Performance-vesting New Hire Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share price (in dollars per share)			$ 75.00