Discontinued Operations (Narrative) (Details) $ in Millions	Mar. 31, 2020 USD ($)
Discontinued Operations [Abstract]
Book value of asset reclassified to current assets held for sale	$ 6

Book Value Of Asset Reclassified To Current Assets Held For Sale

No definition available.

Name:	serv_BookValueOfAssetReclassifiedToCurrentAssetsHeldForSale
Namespace Prefix:	serv_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant