Loans and Allowance for Credit Losses (Schedule of Credit Exposure for Loans Based on Original LTV and FICO Score) (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	$ 24,885,988	$ 23,765,053
1-4 single family residential
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	1,201,204	2,919,080
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	3,169,085	1,065,053
Financing Receivable, Originated Two Years before Latest Fiscal Year	922,591	403,294
Financing Receivable, Originated Three Years before Latest Fiscal Year	320,683	233,205
Financing Receivable, Originated Four Years before Latest Fiscal Year	182,814	349,309
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	1,326,460	1,368,284
Financing Receivable, before Allowance for Credit Loss and Fee	7,122,837	6,338,225
FICO, 760 or greater | 1-4 single family residential
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	805,125	2,230,259
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	2,513,045	803,026
Financing Receivable, Originated Two Years before Latest Fiscal Year	721,982	245,942
Financing Receivable, Originated Three Years before Latest Fiscal Year	212,574	125,713
Financing Receivable, Originated Four Years before Latest Fiscal Year	97,076	254,750
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	944,783	937,285
Financing Receivable, before Allowance for Credit Loss and Fee	5,294,585	4,596,975
FICO, 720 to 759 | 1-4 single family residential
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	285,507	562,763
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	485,528	194,068
Financing Receivable, Originated Two Years before Latest Fiscal Year	132,928	91,276
Financing Receivable, Originated Three Years before Latest Fiscal Year	62,301	53,576
Financing Receivable, Originated Four Years before Latest Fiscal Year	45,857	54,080
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	216,047	219,561
Financing Receivable, before Allowance for Credit Loss and Fee	1,228,168	1,175,324
FICO, 719 or less | 1-4 single family residential
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	110,572	126,058
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	170,512	67,959
Financing Receivable, Originated Two Years before Latest Fiscal Year	67,681	66,076
Financing Receivable, Originated Three Years before Latest Fiscal Year	45,808	53,916
Financing Receivable, Originated Four Years before Latest Fiscal Year	39,881	40,479
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	165,630	211,438
Financing Receivable, before Allowance for Credit Loss and Fee	600,084	565,926
Less than 61% [Member] | 1-4 single family residential
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	282,940	1,222,510
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	1,301,279	399,512
Financing Receivable, Originated Two Years before Latest Fiscal Year	354,720	89,078
Financing Receivable, Originated Three Years before Latest Fiscal Year	76,404	54,301
Financing Receivable, Originated Four Years before Latest Fiscal Year	42,864	111,540
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	466,094	476,170
Financing Receivable, before Allowance for Credit Loss and Fee	2,524,301	2,353,111
61% - 70% [Member] | 1-4 single family residential
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	295,206	791,935
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	857,008	269,739
Financing Receivable, Originated Two Years before Latest Fiscal Year	231,732	92,282
Financing Receivable, Originated Three Years before Latest Fiscal Year	80,383	59,425
Financing Receivable, Originated Four Years before Latest Fiscal Year	49,047	66,641
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	310,648	343,654
Financing Receivable, before Allowance for Credit Loss and Fee	1,824,024	1,623,676
71% - 80% [Member] | 1-4 single family residential
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	620,049	899,400
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	975,542	395,726
Financing Receivable, Originated Two Years before Latest Fiscal Year	336,066	212,649
Financing Receivable, Originated Three Years before Latest Fiscal Year	158,406	111,276
Financing Receivable, Originated Four Years before Latest Fiscal Year	86,463	145,413
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	510,633	518,817
Financing Receivable, before Allowance for Credit Loss and Fee	2,687,159	2,283,281
More than 81% [Member] | 1-4 single family residential
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	3,009	5,235
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	35,256	76
Financing Receivable, Originated Two Years before Latest Fiscal Year	73	9,285
Financing Receivable, Originated Three Years before Latest Fiscal Year	5,490	8,203
Financing Receivable, Originated Four Years before Latest Fiscal Year	4,440	25,715
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	39,085	29,643
Financing Receivable, before Allowance for Credit Loss and Fee	87,353	78,157
30 - 59 Days Past Due
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	210,634	208,894
30 - 59 Days Past Due | 1-4 single family residential
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	12,752	32,307
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	16,432	2,705
Financing Receivable, Originated Two Years before Latest Fiscal Year	3,266	5,482
Financing Receivable, Originated Three Years before Latest Fiscal Year	2,953	1,942
Financing Receivable, Originated Four Years before Latest Fiscal Year	1,854	5,831
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	5,739	4,825
Financing Receivable, before Allowance for Credit Loss and Fee	42,996	53,092
60 - 89 Days Past Due
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	104,171	155,449
60 - 89 Days Past Due | 1-4 single family residential
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	252	605
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	1,196	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	229	1,750
Financing Receivable, Originated Three Years before Latest Fiscal Year	1,347	1,988
Financing Receivable, Originated Four Years before Latest Fiscal Year	0	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	1,052	1,307
Financing Receivable, before Allowance for Credit Loss and Fee	4,076	5,650
90 Days or More Past Due
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	551,169	798,475
90 Days or More Past Due | 1-4 single family residential
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	2,589	1,407
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	2,158	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	2,173	609
Financing Receivable, Originated Three Years before Latest Fiscal Year	360	5,100
Financing Receivable, Originated Four Years before Latest Fiscal Year	3,069	1,064
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	4,606	9,308
Financing Receivable, before Allowance for Credit Loss and Fee	$ 14,955	$ 17,488