Loans and Allowance for Loan Losses, Past Due (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		12 Months Ended
	Jun. 30, 2013		Dec. 31, 2012
Aging of the recorded investment in past due loans [Abstract]
30-59 Days Past Due	$ 9,309		$ 8,115
60-89 Days Past Due	2,876		3,322
90+ Days Past Due	30,577		36,609
Total 30+ days Past Due	42,762		48,046
Current	2,719,664		2,636,687
Total loans	2,762,426		2,684,733
Loans that are 90 days past due and still accruing interest	0		0
Number of days past due	90 days		90 days
Commercial [Member]
Aging of the recorded investment in past due loans [Abstract]
Total loans	216,977		219,577
Commercial [Member] | Commercial Real Estate [Member]
Aging of the recorded investment in past due loans [Abstract]
30-59 Days Past Due	1,986		0
60-89 Days Past Due	112		0
90+ Days Past Due	4,709		5,923
Total 30+ days Past Due	6,807		5,923
Current	182,871		180,208
Total loans	189,678		186,131
Commercial [Member] | Other [Member]
Aging of the recorded investment in past due loans [Abstract]
30-59 Days Past Due	0		0
60-89 Days Past Due	0		0
90+ Days Past Due	123		4
Total 30+ days Past Due	123		4
Current	27,176		33,442
Total loans	27,299		33,446
Real Estate Mortgage - 1 to 4 Family [Member]
Aging of the recorded investment in past due loans [Abstract]
Total loans	2,539,905		2,460,577
Real Estate Mortgage - 1 to 4 Family [Member] | First Mortgages [Member]
Aging of the recorded investment in past due loans [Abstract]
30-59 Days Past Due	6,364		7,226
60-89 Days Past Due	2,171		2,700
90+ Days Past Due	22,368		26,731
Total 30+ days Past Due	30,903		36,657
Current	2,132,712		2,053,321
Total loans	2,163,615		2,089,978
Real Estate Mortgage - 1 to 4 Family [Member] | Home Equity Loans [Member]
Aging of the recorded investment in past due loans [Abstract]
30-59 Days Past Due	112		177
60-89 Days Past Due	40		216
90+ Days Past Due	398		464
Total 30+ days Past Due	550		857
Current	41,169		35,833
Total loans	41,719		36,690
Real Estate Mortgage - 1 to 4 Family [Member] | Home Equity Lines of Credit [Member]
Aging of the recorded investment in past due loans [Abstract]
30-59 Days Past Due	791		663
60-89 Days Past Due	523		379
90+ Days Past Due	2,972		3,486
Total 30+ days Past Due	4,286		4,528
Current	330,285		329,381
Total loans	334,571		333,909
Installment [Member]
Aging of the recorded investment in past due loans [Abstract]
30-59 Days Past Due	56		49
60-89 Days Past Due	30		27
90+ Days Past Due	7		1
Total 30+ days Past Due	93		77
Current	5,451		4,502
Total loans	5,544		4,579
New York and Other States [Member]
Aging of the recorded investment in past due loans [Abstract]
30-59 Days Past Due	8,716		7,185
60-89 Days Past Due	2,632		2,841
90+ Days Past Due	25,731		28,078
Total 30+ days Past Due	37,079		38,104
Current	2,337,130		2,317,862
Total loans	2,374,209	[1]	2,355,966	[1]
New York and Other States [Member] | Commercial [Member]
Aging of the recorded investment in past due loans [Abstract]
Total loans	195,556		200,630
New York and Other States [Member] | Commercial [Member] | Commercial Real Estate [Member]
Aging of the recorded investment in past due loans [Abstract]
30-59 Days Past Due	1,986		0
60-89 Days Past Due	112		0
90+ Days Past Due	4,126		3,225
Total 30+ days Past Due	6,224		3,225
Current	162,084		164,024
Total loans	168,308	[1]	167,249	[1]
New York and Other States [Member] | Commercial [Member] | Other [Member]
Aging of the recorded investment in past due loans [Abstract]
30-59 Days Past Due	0		0
60-89 Days Past Due	0		0
90+ Days Past Due	123		4
Total 30+ days Past Due	123		4
Current	27,125		33,377
Total loans	27,248	[1]	33,381	[1]
New York and Other States [Member] | Real Estate Mortgage - 1 to 4 Family [Member] | First Mortgages [Member]
Aging of the recorded investment in past due loans [Abstract]
30-59 Days Past Due	5,780		6,364
60-89 Days Past Due	1,927		2,248
90+ Days Past Due	18,525		21,341
Total 30+ days Past Due	26,232		29,953
Current	1,806,980		1,784,261
Total loans	1,833,212	[1]	1,814,214	[1]
New York and Other States [Member] | Real Estate Mortgage - 1 to 4 Family [Member] | Home Equity Loans [Member]
Aging of the recorded investment in past due loans [Abstract]
30-59 Days Past Due	112		177
60-89 Days Past Due	40		216
90+ Days Past Due	398		464
Total 30+ days Past Due	550		857
Current	38,958		34,744
Total loans	39,508	[1]	35,601	[1]
New York and Other States [Member] | Real Estate Mortgage - 1 to 4 Family [Member] | Home Equity Lines of Credit [Member]
Aging of the recorded investment in past due loans [Abstract]
30-59 Days Past Due	791		604
60-89 Days Past Due	523		350
90+ Days Past Due	2,552		3,044
Total 30+ days Past Due	3,866		3,998
Current	297,157		297,340
Total loans	301,023	[1]	301,338	[1]
New York and Other States [Member] | Installment [Member]
Aging of the recorded investment in past due loans [Abstract]
30-59 Days Past Due	47		40
60-89 Days Past Due	30		27
90+ Days Past Due	7		0
Total 30+ days Past Due	84		67
Current	4,826		4,116
Total loans	4,910	[1]	4,183	[1]
Florida [Member]
Aging of the recorded investment in past due loans [Abstract]
30-59 Days Past Due	593		930
60-89 Days Past Due	244		481
90+ Days Past Due	4,846		8,531
Total 30+ days Past Due	5,683		9,942
Current	382,534		318,825
Total loans	388,217		328,767
Florida [Member] | Commercial [Member]
Aging of the recorded investment in past due loans [Abstract]
Total loans	21,421		18,947
Florida [Member] | Commercial [Member] | Commercial Real Estate [Member]
Aging of the recorded investment in past due loans [Abstract]
30-59 Days Past Due	0		0
60-89 Days Past Due	0		0
90+ Days Past Due	583		2,698
Total 30+ days Past Due	583		2,698
Current	20,787		16,184
Total loans	21,370		18,882
Florida [Member] | Commercial [Member] | Other [Member]
Aging of the recorded investment in past due loans [Abstract]
30-59 Days Past Due	0		0
60-89 Days Past Due	0		0
90+ Days Past Due	0		0
Total 30+ days Past Due	0		0
Current	51		65
Total loans	51		65
Florida [Member] | Real Estate Mortgage - 1 to 4 Family [Member] | First Mortgages [Member]
Aging of the recorded investment in past due loans [Abstract]
30-59 Days Past Due	584		862
60-89 Days Past Due	244		452
90+ Days Past Due	3,843		5,390
Total 30+ days Past Due	4,671		6,704
Current	325,732		269,060
Total loans	330,403		275,764
Florida [Member] | Real Estate Mortgage - 1 to 4 Family [Member] | Home Equity Loans [Member]
Aging of the recorded investment in past due loans [Abstract]
30-59 Days Past Due	0		0
60-89 Days Past Due	0		0
90+ Days Past Due	0		0
Total 30+ days Past Due	0		0
Current	2,211		1,089
Total loans	2,211		1,089
Florida [Member] | Real Estate Mortgage - 1 to 4 Family [Member] | Home Equity Lines of Credit [Member]
Aging of the recorded investment in past due loans [Abstract]
30-59 Days Past Due	0		59
60-89 Days Past Due	0		29
90+ Days Past Due	420		442
Total 30+ days Past Due	420		530
Current	33,128		32,041
Total loans	33,548		32,571
Florida [Member] | Installment [Member]
Aging of the recorded investment in past due loans [Abstract]
30-59 Days Past Due	9		9
60-89 Days Past Due	0		0
90+ Days Past Due	0		1
Total 30+ days Past Due	9		10
Current	625		386
Total loans	$ 634		$ 396

[1] Includes New York, New Jersey, Vermont and Massachusetts.