Investment Securities (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2013

Dec. 31, 2012

Investments, Debt and Equity Securities [Abstract]

Schedule Of Investment Securities

Investment securities at September 30, 2013, were as follows:

Securities Available-for-Sale (In thousands)	Amortized Cost		Gross Unrealized Holding  Gains		Gross Unrealized Holding  Losses		Estimated  Fair Value
Obligations of U.S. Treasury and other U.S. Government sponsored entities	$	645,631	$	115	$	40,001	$	605,745
Obligations of states and political subdivisions	220		1		—		221
U.S. Government sponsored entities' asset-backed securities	519,917		10,330		9,222		521,025
Other equity securities	1,120		1,372		—		2,492
Total	$	1,166,888	$	11,818	$	49,223	$	1,129,483

Securities Held-to-Maturity (In thousands)	Amortized Cost		Gross Unrecognized Holding  Gains		Gross Unrecognized Holding  Losses		Estimated Fair Value
Obligations of states and political subdivisions	$	240	$	1	$	—	$	241
U.S. Government sponsored entities' asset-backed securities	193,757		5,958		15		199,700
Total	$	193,997	$	5,959	$	15	$	199,941

Investment securities at December 31, 2012, were as follows:

Securities Available-for-Sale (In thousands)	Amortized  cost		Gross unrealized holding gains		Gross unrealized holding losses		Estimated fair value
Obligations of U.S. Treasury and other U.S. Government sponsored entities	$	695,655	$	1,352	$	1,280	$	695,727
Obligations of states and political subdivisions	984		19		—		1,003
U.S. Government sponsored entities' asset-backed securities	401,882		14,067		447		415,502
Other equity securities	1,137		1,085		—		2,222
Total	$	1,099,658	$	16,523	$	1,727	$	1,114,454

Securities Held-to-Maturity (In thousands)	Amortized  cost		Gross unrecognized holding gains		Gross unrecognized holding losses		Estimated fair value
Obligations of states and political subdivisions	$	570	$	2	$	—	$	572
U.S. Government sponsored entities' asset-backed securities	400,820		9,351		38		410,133
Total	$	401,390	$	9,353	$	38	$	410,705

Schedule Of Unrealized Loss On Securities

Securities with unrealized losses at September 30, 2013, were as follows:

	Unrealized loss position for less than 12 months				Unrealized loss position for 12 months or longer				Total
(In thousands)	Fair value		Unrealized losses		Fair value		Unrealized losses		Fair value		Unrealized losses
Securities Available-for-Sale
Obligations of U.S. Treasury and other U.S. Government agencies	$	580,631	$	40,001	$	—	$	—	$	580,631	$	40,001
U.S. Government agencies' asset-backed securities	$	261,211	$	9,222	$	—	$	—	$	261,211	$	9,222
Total	$	841,842	$	49,223	$	—	$	—	$	841,842	$	49,223
Securities Held-to-Maturity
U.S. Government sponsored entities' asset-backed securities	$	5,817	$	15	$	—	$	—	$	5,817	$	15

Securities with unrealized losses at December 31, 2012, were as follows:

	Unrealized loss position for less than 12 months				Unrealized loss position for 12 months or longer				Total
(In thousands)	Fair value		Unrealized losses		Fair value		Unrealized losses		Fair value		Unrealized losses
Securities Available-for-Sale
Obligations of U.S. Treasury and other U.S. Government sponsored entities	$	177,470	$	1,280	$	—	$	—	$	177,470	$	1,280
U.S. Government sponsored entities' asset-backed securities	123,631		447		—		—		123,631		447
Total	$	301,101	$	1,727	$	—	$	—	$	301,101	$	1,727
Securities Held-to-Maturity
U.S. Government sponsored entities' asset-backed securities	$	10,120	$	38	$	—	$	—	$	10,120	$	38

Amortized Cost And Estimated Fair Value Of Investments In Debt Securities By Contractual Maturity

The amortized cost and estimated fair value of investments in debt securities at September 30, 2013, are shown in the following table by contractual maturity or the expected call date, except for asset-backed securities, which are shown as a single total, due to the unpredictability of the timing of principal repayments.

Securities Available-for-Sale (In thousands)	Amortized cost		Fair value
U.S. Treasury and sponsored entities' obligations:
Due within one year	$	25,000	$	25,115
Due one through five years	100,000		96,715
Due five through ten years	396,881		372,909
Due in over ten years	123,750		111,006
Total	$	645,631	$	605,745
Obligations of states and political subdivisions:
Due within one year	$	220	$	221
U.S. Government sponsored entities' asset-backed securities:	$	519,917	$	521,025

Securities Held-to-Maturity (In thousands)	Amortized cost		Fair value
Obligations of state and political subdivisions:
Due within one year	$	240	$	241
U.S. Government sponsored entities' asset-backed securities	$	193,757	$	199,700