Subsequent Event (Details) $ in Millions	Feb. 29, 2016 USD ($)
Subsequent Events [Abstract]
Bank loan borrowings	$ 266.0

The net cash inflow resulting from receipt of cash drawn down under Ultra Resources senior unsecured credit agreement.

No definition available.

Name:	upl_ProceedsFromDepositOnBankLoan
Namespace Prefix:	upl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant