Goodwill and Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2011

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Goodwill

The following table summarizes the changes in goodwill:

	2011		2010		2009
	(in thousands)
Balance at beginning of year	$	535,518	$	534,862	$	534,385
Other goodwill additions, net	487		656		477
Balance at end of year	$	536,005	$	535,518	$	534,862

Schedule of Finite-Lived Intangible Assets by Major Class

The following table summarizes intangible assets as of December 31:

	2011							2010
	Gross		Accumulated Amortization			Net		Gross		Accumulated Amortization			Net
	(in thousands)
Amortizing:
Core deposit	$	50,279	$	(44,134	)	$	6,145	$	50,279	$	(40,475	)	$	9,804
Other	11,403		(10,607		)	796		11,878		(10,484		)	1,394
Total amortizing	61,682		(54,741		)	6,941		62,157		(50,959		)	11,198
Non-amortizing	1,263		—			1,263		1,263		—			1,263
	$	62,945	$	(54,741	)	$	8,204	$	63,420	$	(50,959	)	$	12,461

Schedule of Expected Amortization Expense

Core deposit intangible assets are amortized using an accelerated method over the estimated remaining life of the acquired core deposits. As of December 31, 2011, these assets had a weighted average remaining life of approximately four years. Other amortizing intangible assets, consisting primarily of premiums paid on branch acquisitions in prior years that did not qualify for business combinations accounting under FASB ASC Topic 810, had a weighted average remaining life of three years. All other amortizing intangible assets had a weighted average remaining life of approximately five years. Amortization expense related to intangible assets totaled $4.3 million, $5.2 million and $5.7 million in 2011, 2010 and 2009, respectively.

Amortization expense for the next five years is expected to be as follows (in thousands):

Year
2012	$	3,008
2013	2,240
2014	1,340
2015	310
2016	43