Recently Adopted Accounting Pronouncements - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2021
Accounting Changes And Error Corrections [Abstract]
Accounting Standards Update [Extensible List]	plpc:AccountingStandardsUpdate202101Member
Change in accounting principle, accounting standards update, adopted [true false]	true
Change in accounting principle, accounting standards update, adoption date	Jan. 01, 2021
Change in accounting principle, accounting standards update, immaterial effect [true false]	true