Loans Receivable, Net (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Allowance for loan and lease losses
Balance at beginning of period	$ 130,835	$ 136,586	$ 130,854	$ 137,516
Provision for loan losses	1,078	7,925	3,178	16,550
Charge-offs	(2,271)	(8,679)	(5,885)	(19,737)
Recoveries	1,241	1,627	2,736	3,130
Balance at end of period	130,883	137,459	130,883	137,459
Residential Real Estate [Member]
Allowance for loan and lease losses
Balance at beginning of period	15,411	19,003	15,482	17,227
Provision for loan losses	(509)	22	(486)	2,085
Charge-offs	(172)	(953)	(349)	(1,320)
Recoveries	67	67	150	147
Balance at end of period	14,797	18,139	14,797	18,139
Commercial Real Estate [Member]
Allowance for loan and lease losses
Balance at beginning of period	73,335	73,240	74,398	76,920
Provision for loan losses	520	10,374	(432)	13,010
Charge-offs	(538)	(5,549)	(1,303)	(12,534)
Recoveries	568	1,033	1,222	1,702
Balance at end of period	73,885	79,098	73,885	79,098
Other Commercial [Member]
Allowance for loan and lease losses
Balance at beginning of period	22,481	22,444	21,567	20,833
Provision for loan losses	1,880	(1,255)	3,579	1,304
Charge-offs	(594)	(887)	(1,752)	(2,356)
Recoveries	349	268	722	789
Balance at end of period	24,116	20,570	24,116	20,570
Home Equity [Member]
Allowance for loan and lease losses
Balance at beginning of period	10,833	13,364	10,659	13,616
Provision for loan losses	(1,016)	(1,471)	441	(470)
Charge-offs	(291)	(1,077)	(1,629)	(2,358)
Recoveries	100	88	155	116
Balance at end of period	9,626	10,904	9,626	10,904
Other Consumer [Member]
Allowance for loan and lease losses
Balance at beginning of period	8,775	8,535	8,748	8,920
Provision for loan losses	203	255	76	621
Charge-offs	(676)	(213)	(852)	(1,169)
Recoveries	157	171	487	376
Balance at end of period	$ 8,459	$ 8,748	$ 8,459	$ 8,748