Subsequent Event (Details) (Subsequent Event [Member], USD $) In Millions, unless otherwise specified	6 Months Ended
Jun. 30, 2013
Subsequent Event [Member]
Subsequent Event [Line Items]
Agreement to sell operations center	$ 5.0
Carrying value of building to be used as a branch location	$ 3.2

Refers to the estimated purchase price to be received from a third party for a building the Company had planned to utilize as a regional operations center in Florida.

No definition available.

Name:	trst_AgreementToSellOperationsCenter
Namespace Prefix:	trst_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration