Held-to-Maturity (HTM) Securities (Narrative) (Details) (MBS [Member], USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
MBS [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity Securities, Premium (Discounts), Net	$ 0.4	$ (2.3)

Held-to-maturity Securities, Premium (Discounts), Net

No definition available.

Name:	fhlbpgh_HeldToMaturitySecuritiesPremiumDiscountsNet
Namespace Prefix:	fhlbpgh_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant