Resale and Repurchase Agreements (Tables)

3 Months Ended

Mar. 31, 2018

Resale and Repurchase Agreements [Abstract]

Resale and Repurchase Agreements [Table Text Block]

								Gross Amounts Not Offset in the Balance Sheet
(In thousands)	Gross Amount Recognized		Gross Amounts Offset in the Balance Sheet			Net Amounts Presented in the Balance Sheet		Financial Instruments Available for Offset		Securities Collateral Received/Pledged			Net Amount
March 31, 2018
Total resale agreements, subject to master netting arrangements	$	1,350,000	$	(650,000	)	$	700,000	$	—	$	(700,000	)	$	—
Total repurchase agreements, subject to master netting arrangements	1,677,389		(650,000		)	1,027,389		—		(1,027,389		)	—
December 31, 2017
Total resale agreements, subject to master netting arrangements	$	1,350,000	$	(650,000	)	$	700,000	$	—	$	(700,000	)	$	—
Total repurchase agreements, subject to master netting arrangements	1,954,768		(650,000		)	1,304,768		—		(1,304,768		)	—

Schedule of Underlying Assets of Repurchase Agreements [Table Text Block]

	Remaining Contractual Maturity of the Agreements
(In thousands)	Overnight and continuous		Up to 90 days		Greater than 90 days		Total
March 31, 2018
Repurchase agreements, secured by:
U.S. government and federal agency obligations	$	217,927	$	100,000	$	350,000	$	667,927
Government-sponsored enterprise obligations	91,930		—		—		91,930
Agency mortgage-backed securities	486,517		16,500		200,000		703,017
Non-agency mortgage-backed securities	13,514		—		—		13,514
Asset-backed securities	73,542		65,000		—		138,542
Other debt securities	62,459		—		—		62,459
Total repurchase agreements, gross amount recognized	$	945,889	$	181,500	$	550,000	$	1,677,389
December 31, 2017
Repurchase agreements, secured by:
U.S. government and federal agency obligations	$	271,820	$	1,731	$	450,000	$	723,551
Government-sponsored enterprise obligations	149,111		—		—		149,111
Agency mortgage-backed securities	737,975		9,750		200,000		947,725
Asset-backed securities	89,601		30,000		—		119,601
Other debt securities	14,780		—		—		14,780
Total repurchase agreements, gross amount recognized	$	1,263,287	$	41,481	$	650,000	$	1,954,768