ALLL Activity (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Allowance for loan and lease losses
Balance at beginning of period	$ 129,753	$ 130,351
Provision for loan losses	765	1,122
Charge-offs	(1,297)	(1,586)
Recoveries	635	842
Balance at end of period	129,856	130,729
Residential Real Estate
Allowance for loan and lease losses
Balance at beginning of period	14,680	14,067
Provision for loan losses	440	(178)
Charge-offs	(14)	(36)
Recoveries	25	213
Balance at end of period	15,131	14,066
Commercial Real Estate
Allowance for loan and lease losses
Balance at beginning of period	67,799	70,332
Provision for loan losses	(286)	40
Charge-offs	(445)	(181)
Recoveries	259	380
Balance at end of period	67,327	70,571
Other Commercial
Allowance for loan and lease losses
Balance at beginning of period	30,891	28,630
Provision for loan losses	1,112	933
Charge-offs	(694)	(1,163)
Recoveries	206	84
Balance at end of period	31,515	28,484
Home Equity
Allowance for loan and lease losses
Balance at beginning of period	9,963	9,299
Provision for loan losses	(459)	203
Charge-offs	(31)	(113)
Recoveries	46	37
Balance at end of period	9,519	9,426
Other Consumer
Allowance for loan and lease losses
Balance at beginning of period	6,420	8,023
Provision for loan losses	(42)	124
Charge-offs	(113)	(93)
Recoveries	99	128
Balance at end of period	$ 6,364	$ 8,182

A valuation allowance for financing receivables that are expected to be uncollectible.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(1)

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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(4)

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Amount of direct write-downs of financing receivables charged against the allowance.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 11

-Article 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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