Fair Value (Details) - Fair Value Measurements - USD ($) $ in Thousands		Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014
Trading securities:
Total trading securities		$ 17,693		$ 16,894
Securities available-for-sale:
CDOs		30,431	$ 30,757	31,529	$ 32,004	$ 33,928	$ 33,774
Total securities available-for-sale		1,773,759		1,306,636
Mortgage servicing rights (MSRs)		4,938	$ 5,022	1,853	$ 1,820	$ 1,773	$ 1,728
Level 1
Trading securities:
Money market funds		1,517		2,530
Mutual funds		16,176		14,364
Total trading securities		17,693		16,894
Securities available-for-sale:
U.S. treasury securities		38,889		16,980
U.S. agency securities		0		0
CMOs		0		0
MBSs		0		0
Municipal securities		0		0
CDOs		0		0
Equity securities		0		0
Total securities available-for-sale		38,889		16,980
Mortgage servicing rights (MSRs)	[1]	0		0
Derivative assets	[1]	0		0
Liabilities:
Derivative liabilities	[2]	0		0
Level 2
Trading securities:
Money market funds		0		0
Mutual funds		0		0
Total trading securities		0		0
Securities available-for-sale:
U.S. treasury securities		0		0
U.S. agency securities		199,231		86,643
CMOs		920,735		687,185
MBSs		286,657		153,530
Municipal securities		294,564		327,570
CDOs		0		0
Equity securities		3,252		3,199
Total securities available-for-sale		1,704,439		1,258,127
Mortgage servicing rights (MSRs)	[1]	0		0
Derivative assets	[1]	52,551		16,233
Liabilities:
Derivative liabilities	[2]	52,043		21,039
Level 3
Trading securities:
Money market funds		0		0
Mutual funds		0		0
Total trading securities		0		0
Securities available-for-sale:
U.S. treasury securities		0		0
U.S. agency securities		0		0
CMOs		0		0
MBSs		0		0
Municipal securities		0		0
CDOs		30,431		31,529
Equity securities		0		0
Total securities available-for-sale		30,431		31,529
Mortgage servicing rights (MSRs)	[1]	4,938		1,853
Derivative assets	[1]	0		0
Liabilities:
Derivative liabilities	[2]	$ 0		$ 0

[1] Included in other assets in the Consolidated Statements of Financial Condition.

[2] Included in other liabilities in the Consolidated Statements of Financial Condition.