Note D - Marketable Equity Securities - Unrealized Gains and Losses on Marketable Equity Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Gross unrealized gains	$ 6,803	$ 5,668
Gross unrealized losses	3,063	3,721
Net unrealized gains	$ 3,740	$ 1,947

The amount of accumulated unrealized gain (loss) on equity securities.

No definition available.

Name:	ptsi_EquitySecuritiesFVNIAccumulatedUnrealizedGainLoss
Namespace Prefix:	ptsi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant