Investment in Securities (Tables)

6 Months Ended

Jun. 30, 2012

Investments, Debt and Equity Securities [Abstract]

Available-for-sale Securities [Table Text Block]

The amortized cost, gross unrealized gains, gross unrealized losses and fair value of investment securities are summarized as follows:

	June 30, 2012
			Gross		Gross
	Amortized		Unrealized		Unrealized
(In thousands)	Cost		Gains		Losses		Fair Value
State and political subdivisions	$	299,031	$	18,648	$	313	$	317,366
Certificates of deposit		5,423		—		—		5,423
Total	$	304,454	$	18,648	$	313	$	322,789

	December 31, 2011
			Gross		Gross
	Amortized		Unrealized		Unrealized
(In thousands)	Cost		Gains		Losses		Fair Value
State and political subdivisions	$	287,585	$	19,797	$	20	$	307,362
Certificates of deposit		3,250		—		—		3,250
Total	$	290,835	$	19,797	$	20	$	310,612

Schedule of Unrealized Loss on Investments [Table Text Block]

The fair values of securities with unrealized losses are as follows:

	June 30, 2012
	Less than 12 months				12 months or more				Total
	Estimated		Unrealized		Estimated		Unrealized		Estimated		Unrealized
(In thousands)	fair value		losses		fair value		losses		Fair value		Losses
State and political
subdivisions	$	39,964	$	313	$	—	$	—	$	39,964	$	313
Certificates of deposit		—		—		—		—		—		—
Total	$	39,964	$	313	$	—	$	—	$	39,964	$	313

	December 31, 2011
	Less than 12 months				12 months or more				Total
	Estimated		Unrealized		Estimated		Unrealized		Estimated		Unrealized
(In thousands)	fair value		losses		fair value		losses		Fair value		Losses
State and political
subdivisions	$	4,362	$	20	$	—	$	—	$	4,362	$	20
Certificates of deposit		—		—		—		—		—		—
Total	$	4,362	$	20	$	—	$	—	$	4,362	$	20

Schedule Of Amortized Cost And Fair Value Table Text Block

The amortized cost and fair value of investment securities by contractual maturity are shown in the following table.

	June 30, 2012
(In thousands)	Amortized Cost		Fair Value
Due in 1 year or less	$	9,303	$	9,404
Due after 1 year through 5 years		55,153		59,392
Due after 5 years through 10 years		138,102		146,603
Due after 10 years		101,896		107,390
Total	$	304,454	$	322,789