Investments (Tables)

9 Months Ended

Sep. 30, 2014

Investments [Abstract]

Aggregate Values And Unrealized Gains And Losses Of Investment Securities

The amortized cost and fair value of investment securities classified as available for sale and held to maturity at September 30, 2014 and December 31, 2013, are as follows:

	September 30, 2014
(Dollars in thousands)	Cost		Gross unrealized gains		Gross unrealized losses		Fair value
Investment securities available for sale
U.S. Treasury	$	1,888,647	$	583	$	1,420	$	1,887,810
Government agency	1,128,752		1,294		393		1,129,653
Mortgage-backed securities	2,591,641		7,322		21,498		2,577,465
Equity securities	543		29,485		—		30,028
Municipal securities	125		1		—		126
Other	23,012		—		—		23,012
Total investment securities available for sale	$	5,632,720	$	38,685	$	23,311	$	5,648,094
	December 31, 2013
	Cost		Gross unrealized gains		Gross unrealized losses		Fair value
U.S. Treasury	$	373,223	$	259	$	45	$	373,437
Government agency	2,543,223		1,798		792		2,544,229
Mortgage-backed securities	2,486,297		4,526		43,950		2,446,873
Equity securities	543		21,604		—		22,147
Municipal securities	186		1		—		187
Other	863		—		33		830
Total investment securities available for sale	$	5,404,335	$	28,188	$	44,820	$	5,387,703
	September 30, 2014
	Cost		Gross unrealized gains		Gross unrealized losses		Fair value
Investment securities held to maturity
Mortgage-backed securities	$	607	$	31	$	—	$	638
	December 31, 2013
	Cost		Gross unrealized gains		Gross unrealized losses		Fair value
Mortgage-backed securities	$	907	$	67	$	—	$	974

Investment Securities Maturity Information

The following table provides the amortized cost and fair value by contractual maturity. Expected maturities will differ from contractual maturities on certain securities because borrowers and issuers may have the right to call or prepay obligations with or without prepayment penalties. Repayments of mortgage-backed securities are dependent on the repayments of the underlying loan balances. Equity securities do not have a stated maturity date.

	September 30, 2014				December 31, 2013
(Dollars in thousands)	Cost		Fair value		Cost		Fair value
Investment securities available for sale
Non-amortizing securities maturing in:
One year or less	$	529,931	$	530,363	$	839,956	$	840,883
One through five years	2,487,593		2,487,226		2,077,539		2,077,800
Over 10 years	23,012		23,012		—		—
Mortgage-backed securities	2,591,641		2,577,465		2,486,297		2,446,873
Equity securities	543		30,028		543		22,147
Total investment securities available for sale	$	5,632,720	$	5,648,094	$	5,404,335	$	5,387,703
Investment securities held to maturity
Mortgage-backed securities held to maturity	$	607	$	638	$	907	$	974

Investment Securities With Unrealized Losses

The following table provides information regarding securities with unrealized losses as of September 30, 2014 and December 31, 2013.

	September 30, 2014
	Less than 12 months				12 months or more				Total
(Dollars in thousands)	Fair value		Unrealized losses		Fair value		Unrealized losses		Fair value		Unrealized losses
Investment securities available for sale:
U.S. Treasury	$	999,783	$	1,420	$	—	$	—	$	999,783	$	1,420
Government agency	291,783		393		—		—		291,783		393
Mortgage-backed securities	486,678		2,210		1,090,467		19,288		1,577,145		21,498
Total	$	1,778,244	$	4,023	$	1,090,467	$	19,288	$	2,868,711	$	23,311
	December 31, 2013
	Less than 12 months				12 months or more				Total
	Fair value		Unrealized losses		Fair value		Unrealized losses		Fair value		Unrealized losses
Investment securities available for sale:
U.S. Treasury	$	102,105	$	45	$	—	$	—	$	102,105	$	45
Government agency	780,552		761		29,969		31		810,521		792
Mortgage-backed securities	2,221,213		42,876		26,861		1,074		2,248,074		43,950
Other	830		33		—		—		830		33
Total	$	3,104,700	$	43,715	$	56,830	$	1,105	$	3,161,530	$	44,820