Acquisitions (Narrative) (Detail) (Tower [Member], USD $)	2 Months Ended	3 Months Ended
	Feb. 17, 2012	Mar. 31, 2012
Business Acquisition [Line Items]
Number of shares of Susquehanna common stock for each share of common stock	3.4696
Number of shares of Susquehanna common shares issued	30,800,000
Acquisition of common stock	Feb. 17, 2012
Cash paid per share, acquisition	$ 28.00
Aggregate consideration paid in cash	$ 88,005,000
Assets acquired, total	2,388,122,000
Loans and leases	1,975,488,000
Aggregate liabilities assumed	2,255,413,000
Deposits	2,074,372,000
Transaction added to shareholders equity from acquisition	302,112,000
Net goodwill resulting from acquisition	257,408,000
Additional goodwill recorded	10,547,000
Core deposit intangible, amount to be amortized	24,005,000
Core deposit intangible amortized estimated useful life, years	10 years
Total revenue, net of interest expense		188,500,000
Net income from continuing operations		23,600,000
Real Estate Secured - Commercial [Member]
Business Acquisition [Line Items]
Loans and leases	854,993,000
Commercial Loan And Leases [Member]
Business Acquisition [Line Items]
Loans and leases	136,979,000
Residential Real Estate Loans [Member]
Business Acquisition [Line Items]
Loans and leases	$ 758,803,000