Investment Securities Held-to-Maturity (Tables)

9 Months Ended

Sep. 30, 2013

Text Block [Abstract]

Unrealized Gain (Losses) on Securities

	September 30, 2013								December 31, 2012
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
	(In thousands)
U.S. Government Sponsored Enterprises	$	276,509	$	637	$	1,756	$	275,390	$	17,747	$	19	$	8	$	17,758
U.S. Government Agency and Sponsored Enterprises Mortgage Backed Securities		1,098,203		5,334		7,809		1,095,728		257,760		6,480		74		264,166
Total	$	1,374,712	$	5,971	$	9,565	$	1,371,118	$	275,507	$	6,499	$	82	$	281,924

Company's Securities Held-to-Maturity

The following table shows the maturity distribution of the Company’s securities held-to-maturity at September 30, 2013.

	Amortized Cost		Fair Value
	(In thousands)
Within one year	$	20,936	$	21,053
After one but within five years		680,506		680,292
After five but within ten years		673,002		669,498
More than ten years		268		275
Total	$	1,374,712	$	1,371,118

Unrealized Market Loss of Securities

The following table shows the temporarily impaired securities of the Company’s held-to-maturity portfolio at September 30, 2013. This table shows the unrealized market loss of securities that have been in a continuous unrealized loss position for 12 months or less and a continuous loss position for 12 months and longer. There are 105 and 2 securities that are temporarily impaired for less than 12 months and for 12 months or longer, respectively, out of a total of 279 holdings at September 30, 2013.

	September 30, 2013
	Less Than 12 Months				12 Months or Longer				Total
Temporarily Impaired Investments	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
	(Dollars in thousands)
U.S. Government Sponsored Enterprises	$	147,360	$	1,756	$	—	$	—	$	147,360	$	1,756
U.S. Government Agency and Sponsored Enterprise Mortgage-Backed Securities		579,478		7,621		7,787		188		587,265		7,809
Total temporarily impaired securities	$	726,838	$	9,377	$	7,787	$	188	$	734,625	$	9,565

The following table shows the temporarily impaired securities of the Company’s held-to-maturity portfolio at December 31, 2012. This table shows the unrealized market loss of securities that have been in a continuous unrealized loss position for 12 months or less and a continuous loss position for 12 months and longer. There are 3 and 1 securities that are temporarily impaired for less than 12 months and for 12 months or longer, respectively, out of a total of 96 holdings at December 31, 2012.

	December 31, 2012
	Less Than 12 Months				12 Months or Longer				Total
Temporarily Impaired Investments	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
	(In thousands)
U.S. Government Sponsored Enterprises	$	9,994	$	8	$	—	$	—	$	9,994	$	8
U.S. Government Agency and Sponsored Enterprise Mortgage-Backed Securities		8,936		50		5,371		24		14,307		74
Total temporarily impaired securities	$	18,930	$	58	$	5,371	$	24	$	24,301	$	82