Derivative Instruments (Change In Accumulated Other Comprehensive Income Related To Interest Rate Swaps Designated As Cash Flow Hedge) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2012
Derivative [Line Items]
Amount of gain recognized in AOCI (effective portion)	$ 5,233	$ 6,379
Interest Rate Swap [Member]
Derivative [Line Items]
Unrealized gain at beginning of period	3,210	2,586
Amount of gain recognized in AOCI (effective portion)	5,233	6,379
Amount reclassified from AOCI to interest income on loans	(795)	(1,317)
Unrealized gain at end of period	7,648	7,648
Unrealized gain at beginning of period	1,933	1,557
Amount of gain recognized in AOCI (effective portion)	3,167	3,857
Amount reclassified from AOCI to interest income on loans	(482)	(796)
Unrealized gain at end of period	$ 4,618	$ 4,618

Before tax amount of the income statement impact of the reclassification adjustment of accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges realized in net income. Also includes reclassification adjustments of an entity's share of an equity investee's deferred hedging gain (loss) realized in net income.

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-Glossary Reclassification Adjustments

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+ Details

- Definition

Before tax amount of the change in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Also includes an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

+ References

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+ Details

- Definition

Net of tax amount, before reclassification adjustments, of the change in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Also includes an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

+ References

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