Other Comprehensive Income (Loss) (Changes in Accumulated Other Comprehensive Income (Loss) by Component (Net of Income Taxes)) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Changes in Accumulated Other Comprehensive Income (Loss) by Component [Roll Forward]
Beginning balance			$ (29,819)
Net current period other comprehensive income (loss)	$ 11,745	$ (18,672)	40,824	$ (9,718)
Ending balance	11,005		11,005
Accumulated Other Comprehensive Income (Loss) [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component [Roll Forward]
Beginning balance	(740)	(3,651)	(29,819)	(12,605)
Other comprehensive income (loss) before reclassifications	11,712	(17,493)	40,722	(8,136)
Amounts reclassified from accumulated other comprehensive income (loss)	33	(1,179)	102	(1,582)
Net current period other comprehensive income (loss)	11,745	(18,672)	40,824	(9,718)
Ending balance	11,005	(22,323)	11,005	(22,323)
Net Unrealized Gains (Losses) on Cash Flow Hedges [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component [Roll Forward]
Beginning balance	(12,336)	(12,755)	(12,504)	(12,824)
Other comprehensive income (loss) before reclassifications	0	0	0	0
Amounts reclassified from accumulated other comprehensive income (loss)	39	68	207	137
Net current period other comprehensive income (loss)	39	68	207	137
Ending balance	(12,297)	(12,687)	(12,297)	(12,687)
Net Unrealized Gains (Losses) on Investment Securities Available for Sale [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component [Roll Forward]
Beginning balance	10,747	8,198	(18,222)	(713)
Other comprehensive income (loss) before reclassifications	11,712	(17,636)	40,722	(8,279)
Amounts reclassified from accumulated other comprehensive income (loss)	0	(1,221)	(41)	(1,667)
Net current period other comprehensive income (loss)	11,712	(18,857)	40,681	(9,946)
Ending balance	22,459	(10,659)	22,459	(10,659)
Post-Retirement Unfunded Health Benefit [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component [Roll Forward]
Beginning balance	849	906	907	932
Other comprehensive income (loss) before reclassifications	0	143	0	143
Amounts reclassified from accumulated other comprehensive income (loss)	(6)	(26)	(64)	(52)
Net current period other comprehensive income (loss)	(6)	117	(64)	91
Ending balance	$ 843	$ 1,023	$ 843	$ 1,023

Changes in Accumulated Other Comprehensive Income (Loss) by Component [Roll Forward]

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References

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-Publisher FASB
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-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e637-108580

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax of reclassification adjustments of other comprehensive income (loss).

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