Business Combinations Acquired Impaired Loans Fair Value at Acquisition Date (Details) (Citizens Republic Bancorp, USD $) In Thousands, unless otherwise specified	12 Months Ended		0 Months Ended
Dec. 31, 2013	Apr. 12, 2013	Apr. 12, 2013 non-impaired [Member]
Fair Value Adjustment for Acquired Non-Impaired Loans [Line Items]
Receivables Carrying Value at Acquisition Date			$ 4,017,304
Goodwill, Purchase Accounting Adjustments	5,400		220,015
Business Combination, Acquired Receivables, Fair Value		$ 4,617,004	$ 3,797,289

Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 16

-URI http://asc.fasb.org/extlink&oid=21917927&loc=d3e961-128460

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