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

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Period Type:	instant

- Definition

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

+ References

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

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

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- 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 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 3: 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=56944662&loc=d3e3602-108585

+ Details

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Period Type:	duration

- Details

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- Details

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- Details

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- Details

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ALLL Activity (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
ALLL Activity (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Allowance for loan and lease losses
Balance at beginning of period				$ 129,753				$ 130,351	$ 129,753	$ 130,351	$ 130,854
Provision for loan losses	$ 411	$ 826	$ 282	765	$ 191	$ 360	$ 239	1,122	2,284	1,912	6,887
Charge-offs									(7,002)	(7,603)	(13,643)
Recoveries									4,662	5,093	6,253
Balance at end of period	129,697				129,753				129,697	129,753	130,351
Residential Real Estate
Allowance for loan and lease losses
Balance at beginning of period				14,680				14,067	14,680	14,067	15,482
Provision for loan losses									640	716	(921)
Charge-offs									(985)	(431)	(793)
Recoveries									92	328	299
Balance at end of period	14,427				14,680				14,427	14,680	14,067
Commercial Real Estate
Allowance for loan and lease losses
Balance at beginning of period				67,799				70,332	67,799	70,332	74,398
Provision for loan losses									(696)	(2,877)	(3,670)
Charge-offs									(1,920)	(1,802)	(3,736)
Recoveries									2,694	2,146	3,340
Balance at end of period	67,877				67,799				67,877	67,799	70,332
Other Commercial
Allowance for loan and lease losses
Balance at beginning of period				30,891				28,630	30,891	28,630	21,567
Provision for loan losses									3,030	3,708	10,271
Charge-offs									(2,322)	(3,058)	(4,671)
Recoveries									926	1,611	1,463
Balance at end of period	32,525				30,891				32,525	30,891	28,630
Home Equity
Allowance for loan and lease losses
Balance at beginning of period				9,963				9,299	9,963	9,299	10,659
Provision for loan losses									(480)	1,254	868
Charge-offs									(809)	(1,038)	(2,594)
Recoveries									324	448	366
Balance at end of period	8,998				9,963				8,998	9,963	9,299
Other Consumer
Allowance for loan and lease losses
Balance at beginning of period				$ 6,420				$ 8,023	6,420	8,023	8,748
Provision for loan losses									(210)	(889)	339
Charge-offs									(966)	(1,274)	(1,849)
Recoveries									626	560	785
Balance at end of period	$ 5,870				$ 6,420				$ 5,870	$ 6,420	$ 8,023