Income Taxes (Narrative) (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Effective income tax rates	23.40%	11.70%
Liability for income taxes associated with uncertain tax positions	$ 7,400		$ 7,200
Offsetting tax benefits related to uncertain tax positions	2,500		2,100
Other tax benefits related to interest and penalties of uncertain tax positions	$ 0		$ 0
Unrecognized tax positions increase decrease, months	It is reasonably possible that the amount of the unrecognized benefit with respect to certain of the Company’s unrecognized tax positions may increase or decrease within the next 12 months. Any such change may be the result of ongoing audits or the expiration of federal and state statutes of limitations for the assessment of taxes

Offsetting tax benefits to liability for income taxes associated with uncertain tax positions.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

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- References

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Amount of other current and other deferred income tax expense (benefit) attributable to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32672-109319

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- Definition

Other information relative to a tax position which it is reasonably possible that the total amount of the unrecognized tax benefit will significantly increase or decrease within twelve months of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
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- Definition

Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
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-URI http://asc.fasb.org/extlink&oid=120406818&loc=SL37586934-109318

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