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Income Taxes - Differences between Statutory Federal Income Tax Rate and Effective Income Tax Rate (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Statutory federal income tax rate	21.00%	21.00%	21.00%
State income taxes, net of federal tax benefit	3.40%	3.50%	3.20%
Valuation allowance	(2.90%)	0.10%	(0.60%)
Remeasurement of deferred taxes	(2.80%)	0.00%	0.00%
Tax reserves	0.10%	(0.10%)	(0.40%)
Tax credits	(0.40%)	(0.30%)	(0.40%)
Foreign tax rate effects	1.20%	0.80%	0.40%
Excess tax benefits from stock compensation activity	(4.80%)	(2.90%)	(1.20%)
Other, net	(0.30%)	0.80%	(0.20%)
Effective income tax rate	14.50%	22.90%	21.80%

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Effective Income Tax Rate Reconciliation, Tax Planning, Percent

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Effective Income Tax Rate Reconciliation Tax Reserves

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other adjustments.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to research tax credit.

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