Acquisitions (Details) (Wilmington Trust Corporation [Member], USD $) In Thousands, unless otherwise specified	1 Months Ended
	May 31, 2011	May 16, 2011
Wilmington Trust Corporation [Member]
Purchase price:
Common shares issued (4,694,486 shares)		$ 405,557
Preferred stock purchased from U.S. Treasury		330,000
Total purchase price		735,557
Identifiable assets:
Cash and due from banks		178,940
Interest-bearing deposits at banks		2,606,265
Other short-term investments		57,817
Investment securities		510,390
Loans and leases		6,410,430
Core deposit and other intangibles		112,094
Other assets		969,106
Total identifiable assets		10,845,042
Liabilities:
Deposits		8,864,161
Short-term borrowings		147,752
Long-term borrowings		600,830
Other liabilities		431,812
Total liabilities		10,044,555
Net gain resulting from acquisition	$ 64,930