Loans Receivable, Net (Details) (USD $) In Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Allowance for loan and lease losses
Balance at beginning of the period	$ 140,829	$ 143,600	$ 137,107	$ 142,927
Provision for loan losses	19,150	17,246	38,650	38,156
Charge offs	(21,814)	(20,107)	(38,318)	(41,584)
Recoveries	1,630	926	2,356	2,166
Individually evaluated for impairment	13,895		13,895		16,871
Collectively evaluated for impairment	125,900		125,900		120,236
Balance at end of the period	139,795	141,665	139,795	141,665
Loans Receivable
Individually evaluated for impairment	208,892		208,892		225,052
Collectively evaluated for impairment	3,392,919		3,392,919		3,524,237
Total loans receivable	3,601,811		3,601,811		3,749,289
Residential Real Estate [Member]
Allowance for loan and lease losses
Balance at beginning of the period	17,004		20,957
Provision for loan losses	1,557		(703)
Charge offs	(1,388)		(3,157)
Recoveries	239		315
Individually evaluated for impairment	1,606		1,606		2,793
Collectively evaluated for impairment	15,806		15,806		18,164
Balance at end of the period	17,412		17,412
Loans Receivable
Individually evaluated for impairment	24,963		24,963		29,480
Collectively evaluated for impairment	502,845		502,845		603,397
Total loans receivable	527,808		527,808		632,877
Commercial Real Estate [Member]
Allowance for loan and lease losses
Balance at beginning of the period	80,098		76,147
Provision for loan losses	9,430		23,697
Charge offs	(10,691)		(21,319)
Recoveries	1,048		1,360
Individually evaluated for impairment	9,431		9,431		10,184
Collectively evaluated for impairment	70,454		70,454		65,963
Balance at end of the period	79,885		79,885
Loans Receivable
Individually evaluated for impairment	146,544		146,544		165,784
Collectively evaluated for impairment	1,586,828		1,586,828		1,630,719
Total loans receivable	1,733,372		1,733,372		1,796,503
Other Commercial [Member]
Allowance for loan and lease losses
Balance at beginning of the period	20,960		19,932
Provision for loan losses	3,969		6,607
Charge offs	(5,413)		(7,166)
Recoveries	99		242
Individually evaluated for impairment	1,480		1,480		2,649
Collectively evaluated for impairment	18,135		18,135		17,283
Balance at end of the period	19,615		19,615
Loans Receivable
Individually evaluated for impairment	23,000		23,000		21,358
Collectively evaluated for impairment	634,017		634,017		633,230
Total loans receivable	657,017		657,017		654,588
Home Equity [Member]
Allowance for loan and lease losses
Balance at beginning of the period	14,206		13,334
Provision for loan losses	294		2,415
Charge offs	(971)		(2,303)
Recoveries	96		179
Individually evaluated for impairment	216		216		504
Collectively evaluated for impairment	13,409		13,409		12,830
Balance at end of the period	13,625		13,625
Loans Receivable
Individually evaluated for impairment	9,129		9,129		6,138
Collectively evaluated for impairment	451,379		451,379		476,999
Total loans receivable	460,508		460,508		483,137
Other Consumer [Member]
Allowance for loan and lease losses
Balance at beginning of the period	8,561		6,737
Provision for loan losses	3,900		6,634
Charge offs	(3,351)		(4,373)
Recoveries	148		260
Individually evaluated for impairment	1,162		1,162		741
Collectively evaluated for impairment	8,096		8,096		5,996
Balance at end of the period	9,258		9,258
Loans Receivable
Individually evaluated for impairment	5,256		5,256		2,292
Collectively evaluated for impairment	217,850		217,850		179,892
Total loans receivable	$ 223,106		$ 223,106		$ 182,184