Consolidated Statements of Income and Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
INTEREST INCOME:
Mortgage and other loans and leases	$ 1,553,004	$ 1,467,944	$ 1,417,237
Securities and money market investments	252,156	221,729	165,002
Total interest income	1,805,160	1,689,673	1,582,239
INTEREST EXPENSE:
Interest-bearing checking and money market accounts	174,347	167,972	98,980
Savings accounts	35,705	28,994	28,447
Certificates of deposit	320,234	182,383	102,355
Borrowed funds	317,474	279,329	222,454
Total interest expense	847,760	658,678	452,236
Net interest income	957,400	1,030,995	1,130,003
Net interest income after provision for (recovery of) loan losses	950,295	1,012,739	1,092,761
NON-INTEREST INCOME:
Fee income	29,297	29,765	31,759
Bank-owned life insurance	28,363	28,252	27,133
Net gain (loss) on securities	7,725	(1,994)	29,924
Mortgage banking income			19,337
FDIC indemnification expense			(18,961)
Gain on sale of covered loans and mortgage banking operations			82,026
Other	18,845	35,535	45,662
Total non-interest income	84,230	91,558	216,880
Operating expenses:
Compensation and benefits	301,697	317,496	363,698
Occupancy and equipment	89,174	100,107	98,963
General and administrative	120,347	129,025	178,557
Total operating expenses	511,218	546,628	641,218
Amortization of core deposit intangibles			208
Total non-interest expense	511,218	546,628	641,426
Income before income taxes	523,307	557,669	668,215
Income tax expense	128,264	135,252	202,014
Net income	395,043	422,417	466,201
Preferred stock dividends	32,828	32,828	24,621
Net income available to common shareholders	$ 362,215	$ 389,589	$ 441,580
Basic earnings per common share	$ 0.77	$ 0.79	$ 0.90
Diluted earnings per common share	$ 0.77	$ 0.79	$ 0.90
Net income	$ 395,043	$ 422,417	$ 466,201
Other comprehensive income (loss), net of tax:
Change in net unrealized gain (loss) on securities available for sale, net of tax of $(17,669); $32,166; and $(29,740), respectively	45,934	(49,732)	41,684
Change in the non-credit portion of OTTI losses recognized in other comprehensive income (loss), net of tax of $000; $(821); and $(13), respectively		(821)	20
Change in pension and post-retirement obligations, net of tax of $(5,033); $(4,897); and $(2,234), respectively	11,941	(21,943)	1,585
Change in net unrealized gain (loss) on cash flow hedges, net of tax of $(376)	964
Less: Reclassification adjustment for sales of available-for-sale securities, net of tax of $1,527; $(4); and $1,245, respectively	(3,918)	10	(1,743)
Reclassification adjustment for net gain on cash flow hedges included in net income, net of tax of $43	(111)
Total other comprehensive income (loss), net of tax	54,810	(72,486)	41,546
Total comprehensive income, net of tax	449,853	349,931	507,747
Non-Covered Loans
INTEREST EXPENSE:
Provision for (recovery of) losses	$ 7,105	$ 18,256	60,943
Covered Loans
INTEREST EXPENSE:
Provision for (recovery of) losses			$ (23,701)