Securities (Tables)

6 Months Ended

Jun. 30, 2017

The fair value and net unrealized gain (loss) included in trading securities is as follows (in thousands):



	June 30, 2017					December 31, 2016					June 30, 2016
	Fair Value		Net Unrealized Gain (Loss)			Fair Value		Net Unrealized Gain (Loss)			Fair Value		Net Unrealized Gain (Loss)
U.S. government agency debentures	$	20,954	$	(9	)	$	6,234	$	(4	)	$	18,909	$	(8	)
U.S. government agency residential mortgage-backed securities	365,171		(1,032		)	310,067		635			122,306		363
Municipal and other tax-exempt securities	45,444		230			14,427		50			52,721		262
Other trading securities	9,845		(175		)	6,900		57			17,686		169
Total trading securities	$	441,414	$	(986	)	$	337,628	$	738		$	211,622	$	786

Investment Securities (Held-to-Maturity) [Table Text Block]

The amortized cost and fair values of investment securities are as follows (in thousands):



	June 30, 2017
	Amortized		Fair		Gross Unrealized¹
	Cost		Value		Gain		Loss
Municipal and other tax-exempt	$	267,375	$	270,531	$	3,384	$	(228	)
U.S. government agency residential mortgage-backed securities – Other	18,035		18,642		668		(61		)
Other debt securities	205,016		226,502		22,040		(554		)
Total investment securities	$	490,426	$	515,675	$	26,092	$	(843	)


¹	Gross unrealized gains and losses are not recognized in Accumulated Other Comprehensive Income "AOCI" in the Consolidated Balance Sheets.



	December 31, 2016
	Amortized		Fair		Gross Unrealized¹
	Cost		Value		Gain		Loss
Municipal and other tax-exempt	$	320,364	$	321,225	$	2,272	$	(1,411	)
U.S. government agency residential mortgage-backed securities – Other	20,777		21,473		767		(71		)
Other debt securities	205,004		222,795		18,115		(324		)
Total investment securities	$	546,145	$	565,493	$	21,154	$	(1,806	)


¹	Gross unrealized gains and losses are not recognized in AOCI in the Consolidated Balance Sheets.



	June 30, 2016
	Amortized		Fair		Gross Unrealized¹
	Cost		Value		Gain		Loss
Municipal and other tax-exempt	$	334,551	$	340,700	$	6,234	$	(85	)
U.S. government agency residential mortgage-backed securities – Other	23,750		25,233		1,483		—
Other debt securities	202,410		233,129		30,723		(4		)
Total investment securities	$	560,711	$	599,062	$	38,440	$	(89	)


¹	Gross unrealized gains and losses are not recognized in AOCI in the Consolidated Balance Sheets.

The amortized cost and fair values of investment securities at June 30, 2017, by contractual maturity, are as shown in the following table (dollars in thousands):



	Less than One Year			One to Five Years			Six to Ten Years			Over Ten Years			Total			Weighted Average Maturity²
Municipal and other tax-exempt:
Amortized cost	$	90,415		$	122,560		$	10,739		$	43,661		$	267,375		3.48
Fair value	90,436			122,914			11,220			45,961			270,531
Nominal yield¹	1.66		%	2.12		%	4.88		%	5.05		%	2.55		%
Other debt securities:
Amortized cost	14,286			45,638			130,279			14,813			205,016			6.59
Fair value	14,482			48,973			148,415			14,632			226,502
Nominal yield	3.84		%	4.95		%	5.75		%	4.46		%	5.35		%
Total fixed maturity securities:
Amortized cost	$	104,701		$	168,198		$	141,018		$	58,474		$	472,391		4.83
Fair value	104,918			171,887			159,635			60,593			497,033
Nominal yield	1.95		%	2.89		%	5.69		%	4.90		%	3.77		%
Residential mortgage-backed securities:
Amortized cost													$	18,035		³
Fair value													18,642
Nominal yield⁴													2.76		%
Total investment securities:
Amortized cost													$	490,426
Fair value													515,675
Nominal yield													3.73		%


¹	Calculated on a taxable equivalent basis using a 39 percent effective tax rate.


²	Expected maturities may differ from contractual maturities, because borrowers may have the right to call or prepay obligations with or without penalty.


³	The average expected lives of residential mortgage-backed securities were 4.7 years based upon current prepayment assumptions.


⁴	The nominal yield on residential mortgage-backed securities is based upon prepayment assumptions at the purchase date. Actual yields earned may differ significantly based upon actual prepayments. See Quarterly Financial Summary - Unaudited for current yields on the investment securities portfolio.

Available For Sale Securities [Table Text Block]

The amortized cost and fair value of available for sale securities are as follows (in thousands):



	June 30, 2017
	Amortized		Fair		Gross Unrealized¹
	Cost		Value		Gain		Loss			OTTI²
U.S. Treasury	$	1,000	$	998	$	—	$	(2	)	$	—
Municipal and other tax-exempt	32,885		32,765		293		(413		)	—
Residential mortgage-backed securities:
U. S. government agencies:
FNMA	3,005,920		3,008,531		24,213		(21,602		)	—
FHLMC	1,412,376		1,412,472		7,785		(7,689		)	—
GNMA	938,086		936,365		3,641		(5,362		)	—
Other	25,000		25,009		52		(43		)	—
Total U.S. government agencies	5,381,382		5,382,377		35,691		(34,696		)	—
Private issue:
Alt-A loans	38,334		46,903		8,569		—			—
Jumbo-A loans	48,322		56,480		8,158		—			—
Total private issue	86,656		103,383		16,727		—			—
Total residential mortgage-backed securities	5,468,038		5,485,760		52,418		(34,696		)	—
Commercial mortgage-backed securities guaranteed by U.S. government agencies	2,788,543		2,782,070		7,804		(14,277		)	—
Other debt securities	4,400		4,152		—		(248		)	—
Perpetual preferred stock	12,562		16,568		4,006		—			—
Equity securities and mutual funds	17,572		18,728		1,219		(63		)	—
Total available for sale securities	$	8,325,000	$	8,341,041	$	65,740	$	(49,699	)	$	—

¹ Gross unrealized gain/loss recognized in AOCI in the consolidated balance sheet.

² Amounts represent unrealized loss that remains in AOCI after an other-than-temporary credit loss has been recognized in income.



	December 31, 2016
	Amortized		Fair		Gross Unrealized¹
	Cost		Value		Gain		Loss			OTTI²
U.S. Treasury	$	1,000	$	999	$	—	$	(1	)	$	—
Municipal and other tax-exempt	41,050		40,993		343		(400		)	—
Residential mortgage-backed securities:
U. S. government agencies:
FNMA	3,062,525		3,055,676		25,066		(31,915		)	—
FHLMC	1,534,451		1,531,116		8,475		(11,810		)	—
GNMA	878,375		873,594		2,259		(7,040		)	—
Total U.S. government agencies	5,475,351		5,460,386		35,800		(50,765		)	—
Private issue:
Alt-A loans	44,245		51,512		7,485		—			(218		)
Jumbo-A loans	56,947		64,023		7,092		(16		)	—
Total private issue	101,192		115,535		14,577		(16		)	(218		)
Total residential mortgage-backed securities	5,576,543		5,575,921		50,377		(50,781		)	(218		)
Commercial mortgage-backed securities guaranteed by U.S. government agencies	3,035,750		3,017,933		5,472		(23,289		)	—
Other debt securities	4,400		4,152		—		(248		)	—
Perpetual preferred stock	15,561		18,474		2,913		—			—
Equity securities and mutual funds	17,424		18,357		1,060		(127		)	—
Total available for sale securities	$	8,691,728	$	8,676,829	$	60,165	$	(74,846	)	$	(218	)

¹ Gross unrealized gain/loss recognized in AOCI in the consolidated balance sheet.

² Amounts represent unrealized loss that remains in AOCI after an other-than-temporary credit loss has been recognized in income.



	June 30, 2016
	Amortized		Fair		Gross Unrealized¹
	Cost		Value		Gain		Loss			OTTI²
U.S. Treasury	$	1,000	$	1,004	$	4	$	—		$	—
Municipal and other tax-exempt	50,170		50,262		805		(713		)	—
Residential mortgage-backed securities:
U. S. government agencies:
FNMA	2,908,698		2,988,974		80,549		(273		)	—
FHLMC	1,746,661		1,785,332		38,869		(198		)	—
GNMA	921,928		925,962		4,646		(612		)	—
Total U.S. government agencies	5,577,287		5,700,268		124,064		(1,083		)	—
Private issue:
Alt-A loans	49,522		54,536		5,461		—			(447		)
Jumbo-A loans	65,787		71,777		6,355		(36		)	(329		)
Total private issue	115,309		126,313		11,816		(36		)	(776		)
Total residential mortgage-backed securities	5,692,596		5,826,581		135,880		(1,119		)	(776		)
Commercial mortgage-backed securities guaranteed by U.S. government agencies	2,854,306		2,911,946		57,762		(122		)	—
Other debt securities	4,400		4,151		—		(249		)	—
Perpetual preferred stock	15,562		17,931		2,369		—			—
Equity securities and mutual funds	17,270		18,814		1,558		(14		)	—
Total available for sale securities	$	8,635,304	$	8,830,689	$	198,378	$	(2,217	)	$	(776	)


¹	Gross unrealized gain/loss recognized in AOCI in the consolidated balance sheet.


²	Amounts represent unrealized loss that remains in AOCI after an other-than-temporary credit loss has been recognized in income.

The amortized cost and fair values of available for sale securities at June 30, 2017, by contractual maturity, are as shown in the following table (dollars in thousands):



	Less than One Year			One to Five Years			Six to Ten Years			Over Ten Years				Total			Weighted Average Maturity⁵
U.S. Treasuries:
Amortized cost	$	1,000		$	—		$	—		$	—			$	1,000		0.55
Fair value	998			—			—			—				998
Nominal yield	0.87		%	—		%	—		%	—		%		0.87		%
Municipal and other tax-exempt:
Amortized cost	$	8,981		$	6,380		$	1,028		$	16,496			$	32,885		8.87
Fair value	9,021			6,497			1,081			16,166				32,765
Nominal yield¹	4.24		%	3.91		%	6.72		%	2.28		%	⁶	3.27		%
Commercial mortgage-backed securities:
Amortized cost	$	58,263		$	880,459		$	1,571,735		$	278,086			$	2,788,543		6.98
Fair value	58,147			879,286			1,568,732			275,905				2,782,070
Nominal yield	1.20		%	1.83		%	1.84		%	1.88		%		1.82		%
Other debt securities:
Amortized cost	$	—		$	—		$	—		$	4,400			$	4,400		30.16
Fair value	—			—			—			4,152				4,152
Nominal yield	—		%	—		%	—		%	1.71		%	⁶	1.71		%
Total fixed maturity securities:
Amortized cost	$	68,244		$	886,839		$	1,572,763		$	298,982			$	2,826,828		7.03
Fair value	68,166			885,783			1,569,813			296,223				2,819,985
Nominal yield	1.60		%	1.85		%	1.85		%	1.90		%		1.83		%
Residential mortgage-backed securities:
Amortized cost														$	5,468,038		²
Fair value														5,485,760
Nominal yield⁴														1.94		%
Equity securities and mutual funds:
Amortized cost														$	30,134		³
Fair value														35,296
Nominal yield														—		%
Total available-for-sale securities:
Amortized cost														$	8,325,000
Fair value														8,341,041
Nominal yield														1.90		%


¹	Calculated on a taxable equivalent basis using a 39 percent effective tax rate.


²	The average expected lives of mortgage-backed securities were 3.9 years years based upon current prepayment assumptions.


³	Primarily common stock and preferred stock of corporate issuers with no stated maturity.


⁴	The nominal yield on mortgage-backed securities is based upon prepayment assumptions at the purchase date. Actual yields earned may differ significantly based upon actual prepayments. See Quarterly Financial Summary –– Unaudited following for current yields on available for sale securities portfolio.


⁵	Expected maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without penalty.


⁶	Nominal yield on municipal and other tax-exempt securities and other debt securities with contractual maturity dates over ten years are based on variable rates which generally are reset within 35 days.

Sales of available for sale securities resulted in gains and losses as follows (in thousands):



	Three Months Ended June 30,					Six Months Ended June 30,
	2017			2016		2017			2016
Proceeds	$	460,402		$	325,758	$	700,412		$	795,140
Gross realized gains	2,763			5,326		4,855			9,290
Gross realized losses	(2,383		)	—		(2,426		)	—
Related federal and state income tax expense	148			2,072		945			3,614

Securities Pledged As Collateral [Table Text Block]

A summary of investment and available for sale securities that have been pledged as collateral for repurchase agreements, public trust funds on deposit and for other purposes, as required by law was as follows (in thousands):



	June 30, 2017		Dec. 31, 2016		June 30, 2016
Investment:
Amortized cost	$	251,684	$	322,208	$	287,166
Fair value	255,097		323,808		293,625

Available for sale:
Amortized cost	6,327,666		7,353,116		7,502,361
Fair value	6,317,623		7,327,470		7,657,916

Schedule of Unrealized Loss on Investments [Table Text Block]

Temporarily Impaired Securities as of June 30, 2017

(in thousands):



	Number of Securities	Less Than 12 Months				12 Months or Longer				Total
	Number of Securities	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
Investment:
Municipal and other tax-exempt	82	$	111,078	$	149	$	3,000	$	79	$	114,078	$	228
U.S. government agency residential mortgage-backed securities – Other	1	3,810		61		—		—		3,810		61
Other debt securities	22	8,384		554		—		—		8,384		554
Total investment securities	105	$	123,272	$	764	$	3,000	$	79	$	126,272	$	843



	Number of Securities	Less Than 12 Months				12 Months or Longer				Total
	Number of Securities	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
Available for sale:
U.S. Treasury	1	$	997	$	2	$	—	$	—	$	997	$	2
Municipal and other tax-exempt	13	$	1,957	$	1	$	4,655	$	412	$	6,612	$	413
Residential mortgage-backed securities:
U. S. government agencies:
FNMA	75	1,381,687		20,288		87,371		1,314		1,469,058		21,602
FHLMC	42	731,853		7,213		16,388		476		748,241		7,689
GNMA	21	291,806		3,766		76,605		1,596		368,411		5,362
Other	1	19,957		43		—		—		19,957		43
Total U.S. government agencies	139	2,425,303		31,310		180,364		3,386		2,605,667		34,696
Private issue:
Alt-A loans	—	—		—		—		—		—		—
Jumbo-A loans	—	—		—		—		—		—		—
Total private issue	—	—		—		—		—		—		—
Total residential mortgage-backed securities	139	2,425,303		31,310		180,364		3,386		2,605,667		34,696
Commercial mortgage-backed securities guaranteed by U.S. government agencies	121	1,388,406		12,690		78,828		1,587		1,467,234		14,277
Other debt securities	2	—		—		4,152		248		4,152		248
Perpetual preferred stocks	—	—		—		—		—		—		—
Equity securities and mutual funds	91	1,668		22		887		41		2,555		63
Total available for sale securities	367	$	3,818,331	$	44,025	$	268,886	$	5,674	$	4,087,217	$	49,699

Temporarily Impaired Securities as of December 31, 2016

(In thousands)



	Number of Securities	Less Than 12 Months				12 Months or Longer				Total
	Number of Securities	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
Investment:
Municipal and other tax-exempt	151	$	219,892	$	1,316	$	4,333	$	95	$	224,225	$	1,411
U.S. government agency residential mortgage-backed securities – Other	1	4,358		71		—		—		4,358		71
Other debt securities	41	11,820		322		855		2		12,675		324
Total investment securities	193	$	236,070	$	1,709	$	5,188	$	97	$	241,258	$	1,806



	Number of Securities	Less Than 12 Months				12 Months or Longer				Total
	Number of Securities	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
Available for sale:
U.S. Treasury	1	$	999	$	1	$	—	$	—	$	999	$	1
Municipal and other tax-exempt	24	$	15,666	$	22	$	4,689	$	378	$	20,355	$	400
Residential mortgage-backed securities:
U. S. government agencies:
FNMA	91	1,787,644		30,238		72,105		1,677		1,859,749		31,915
FHLMC	58	964,017		11,210		18,307		600		982,324		11,810
GNMA	31	548,637		6,145		25,796		895		574,433		7,040
Total U.S. government agencies	180	3,300,298		47,593		116,208		3,172		3,416,506		50,765
Private issue¹:
Alt-A loans	5	7,931		174		7,410		44		15,341		218
Jumbo-A loans	1	—		—		6,098		16		6,098		16
Total private issue	6	7,931		174		13,508		60		21,439		234
Total residential mortgage-backed securities	186	3,308,229		47,767		129,716		3,232		3,437,945		50,999
Commercial mortgage-backed securities guaranteed by U.S. government agencies	171	1,904,584		22,987		38,875		302		1,943,459		23,289
Other debt securities	2	—		—		4,152		248		4,152		248
Perpetual preferred stocks	—	—		—		—		—		—		—
Equity securities and mutual funds	104	2,127		41		817		86		2,944		127
Total available for sale securities	488	$	5,231,605	$	70,818	$	178,249	$	4,246	$	5,409,854	$	75,064


¹	Includes securities for which an unrealized loss remains in AOCI after an other-than-temporary credit loss has been recognized in income.

Temporarily Impaired Securities as of June 30, 2016

(In thousands)



	Number of Securities	Less Than 12 Months				12 Months or Longer				Total
	Number of Securities	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
Investment:
Municipal and other tax-exempt	19	$	11,915	$	20	$	4,378	$	65	$	16,293	$	85
U.S. government agency residential mortgage-backed securities – Other	—	—		—		—		—		—		—
Other debt securities	1	—		—		858		4		858		4
Total investment securities	20	$	11,915	$	20	$	5,236	$	69	$	17,151	$	89



	Number of Securities	Less Than 12 Months				12 Months or Longer				Total
	Number of Securities	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
Available for sale:
U.S. Treasury	—	$	—	$	—	$	—	$	—	$	—	$	—
Municipal and other tax-exempt¹	17	$	375	$	—	$	10,289	$	713	$	10,664	$	713
Residential mortgage-backed securities:
U. S. government agencies:
FNMA	4	97,910		267		15,401		6		113,311		273
FHLMC	1	—		—		22,338		198		22,338		198
GNMA	11	349,631		612		—		—		349,631		612
Total U.S. government agencies	16	447,541		879		37,739		204		485,280		1,083
Private issue¹:
Alt-A loans	5	8,513		241		8,291		206		16,804		447
Jumbo-A loans	9	7,076		36		7,877		329		14,953		365
Total private issue	14	15,589		277		16,168		535		31,757		812
Total residential mortgage-backed securities	30	463,130		1,156		53,907		739		517,037		1,895
Commercial mortgage-backed securities guaranteed by U.S. government agencies	11	103,955		37		65,857		85		169,812		122
Other debt securities	2	—		—		4,151		249		4,151		249
Perpetual preferred stocks	—	—		—		—		—		—		—
Equity securities and mutual funds	30	—		—		889		14		889		14
Total available for sale securities	90	$	567,460	$	1,193	$	135,093	$	1,800	$	702,553	$	2,993


¹	Includes securities for which an unrealized loss remains in AOCI after an other-than-temporary credit loss has been recognized in income.

Fair Value Option Securities [Table Text Block]

The fair value and net unrealized gain (loss) included in fair value option securities is as follows (in thousands):



	June 30, 2017				Dec. 31, 2016					June 30, 2016
	Fair Value		Net Unrealized Gain (Loss)		Fair Value		Net Unrealized Gain (Loss)			Fair Value		Net Unrealized Gain (Loss)
U.S. Treasury	$	—	$	—	$	—	$	—		$	25,306	$	(43	)
U.S. government agency residential mortgage-backed securities	445,169		1,247		77,046		(1,777		)	237,959		4,476
Total	$	445,169	$	1,247	$	77,046	$	(1,777	)	$	263,265	$	4,433

Schedule of Restricted Equity Securities [Table Text Block]



	June 30, 2017		Dec. 31, 2016		June 30, 2016
Federal Reserve stock	$	36,676	$	36,498	$	36,283
Federal Home Loan Bank stock	274,113		270,541		283,155
Other	244		201		201
Total	$	311,033	$	307,240	$	319,639

- Definition

Tabular disclosure of available-for-sale securities which includes, but is not limited to, changes in the cost basis and fair value, fair value and gross unrealized gain (loss), fair values by type of security, contractual maturity and classification, amortized cost basis, contracts to acquire securities to be accounted for as available-for-sale, debt maturities, transfers to trading, change in net unrealized holding gain (loss) net of tax, continuous unrealized loss position fair value, aggregate losses qualitative disclosures, other than temporary impairment (OTTI) losses or other disclosures related to available for sale securities.

+ References + Details

- Definition

Tabular disclosure of all investments in certain debt and equity securities for which the entity has the positive intent and ability to hold until maturity.

+ References + Details