Note 10 - Fair Value of Financial Instruments (Details) - Carrying Amounts and Estimated Fair Values of Selected Financial Instruments (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Assets:
Carrying Value	$ 4,891,986	$ 4,721,501
Liabilities:
Carrying Value	4,439,590	4,288,969
Cash and due from banks [Member] | Fair Value, Inputs, Level 1 [Member]
Assets:
Fair Value	30,499	33,485
Cash and due from banks [Member]
Assets:
Carrying Value	30,499	33,485
Fair Value	30,499	33,485
Collateralized Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets:
Fair Value	696,209	756,156
Collateralized Mortgage Backed Securities [Member]
Assets:
Carrying Value	696,209	756,156
Fair Value	696,209	756,156
Other securities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets:
Fair Value	262,097	237,476
Other securities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets:
Fair Value	26,071	24,158
Other securities [Member]
Assets:
Carrying Value	288,168	261,634
Fair Value	288,168	261,634
Loans Held For Sale [Member] | Fair Value, Inputs, Level 3 [Member]
Assets:
Fair Value	1,150	425
Loans Held For Sale [Member]
Assets:
Carrying Value	1,150	425
Fair Value	1,150	425
Loans [Member] | Fair Value, Inputs, Level 3 [Member]
Assets:
Fair Value	3,718,239	3,502,792
Loans [Member]
Assets:
Carrying Value	3,645,634	3,434,178
Fair Value	3,718,239	3,502,792
FHLB-NY stock [Member] | Fair Value, Inputs, Level 2 [Member]
Assets:
Fair Value	45,776	46,025
FHLB-NY stock [Member]
Assets:
Carrying Value	45,776	46,025
Fair Value	45,776	46,025
Interest Rate Swap [Member] | Fair Value, Inputs, Level 2 [Member]
Assets:
Fair Value	174	2,081
Liabilities:
Fair Value	535
Interest Rate Swap [Member]
Assets:
Carrying Value	174	2,081
Fair Value	174	2,081
Liabilities:
Carrying Value	535
Fair Value	535
Other real estate owned [Member] | Fair Value, Inputs, Level 3 [Member]
Assets:
Fair Value	5,792	2,985
Other real estate owned [Member]
Assets:
Carrying Value	5,792	2,985
Fair Value	5,792	2,985
Total Assets, Financial Instruments [Member] | Fair Value, Inputs, Level 1 [Member]
Assets:
Fair Value	30,499	33,485
Total Assets, Financial Instruments [Member] | Fair Value, Inputs, Level 2 [Member]
Assets:
Fair Value	1,004,256	1,041,738
Total Assets, Financial Instruments [Member] | Fair Value, Inputs, Level 3 [Member]
Assets:
Fair Value	3,751,252	3,530,360
Total Assets, Financial Instruments [Member]
Assets:
Carrying Value	4,713,402	4,536,969
Fair Value	4,786,007	4,605,583
Total Liabilities, Financial Instruments [Member] | Fair Value, Inputs, Level 1 [Member]
Liabilities:
Fair Value	2,063,629	2,111,825
Total Liabilities, Financial Instruments [Member] | Fair Value, Inputs, Level 2 [Member]
Liabilities:
Fair Value	2,330,492	2,146,665
Total Liabilities, Financial Instruments [Member] | Fair Value, Inputs, Level 3 [Member]
Liabilities:
Fair Value	29,535	29,570
Total Liabilities, Financial Instruments [Member]
Liabilities:
Carrying Value	4,395,729	4,244,902
Fair Value	4,423,656	4,288,060
Deposits [Member] | Fair Value, Inputs, Level 1 [Member]
Liabilities:
Fair Value	2,063,629	2,111,825
Deposits [Member] | Fair Value, Inputs, Level 2 [Member]
Liabilities:
Fair Value	1,313,839	1,141,436
Deposits [Member]
Liabilities:
Carrying Value	3,363,561	3,232,780
Fair Value	3,377,468	3,253,261
Borrowings [Member] | Fair Value, Inputs, Level 2 [Member]
Liabilities:
Fair Value	1,016,118	1,005,229
Borrowings [Member] | Fair Value, Inputs, Level 3 [Member]
Liabilities:
Fair Value	29,535	29,570
Borrowings [Member]
Liabilities:
Carrying Value	1,031,633	1,012,122
Fair Value	$ 1,045,653	$ 1,034,799