Loans Receivable, Net - Credit Quality Indicators for Commercial Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Credit Quality Indicators By Origination
Total	$ 11,618,731	$ 9,512,810
Commercial Real Estate
Credit Quality Indicators By Origination
Term loans originated in 2020 (year-to-date)	1,023,640
Term loans originated in 2019	1,149,893
Term loans originated in 2018	986,619
Term loans originated in 2017	786,907
Term loans originated in 2016	526,236
Term loans originated in 2015 and prior	1,581,948
Revolving loans	146,574
Total	6,201,817	5,579,307
Commercial Real Estate | Pass
Credit Quality Indicators By Origination
Term loans originated in 2020 (year-to-date)	1,018,529
Term loans originated in 2019	1,141,014
Term loans originated in 2018	947,230
Term loans originated in 2017	756,583
Term loans originated in 2016	507,694
Term loans originated in 2015 and prior	1,546,314
Revolving loans	143,265
Total	6,060,629
Commercial Real Estate | Special Mention
Credit Quality Indicators By Origination
Term loans originated in 2020 (year-to-date)	697
Term loans originated in 2019	335
Term loans originated in 2018	1,190
Term loans originated in 2017	0
Term loans originated in 2016	206
Term loans originated in 2015 and prior	0
Revolving loans	691
Total	3,119
Commercial Real Estate | Substandard
Credit Quality Indicators By Origination
Term loans originated in 2020 (year-to-date)	4,414
Term loans originated in 2019	8,544
Term loans originated in 2018	38,199
Term loans originated in 2017	30,324
Term loans originated in 2016	18,336
Term loans originated in 2015 and prior	35,286
Revolving loans	2,617
Total	137,720
Commercial Real Estate | Doubtful/ Loss
Credit Quality Indicators By Origination
Term loans originated in 2020 (year-to-date)	0
Term loans originated in 2019	0
Term loans originated in 2018	0
Term loans originated in 2017	0
Term loans originated in 2016	0
Term loans originated in 2015 and prior	348
Revolving loans	1
Total	349
Other Commercial
Credit Quality Indicators By Origination
Term loans originated in 2020 (year-to-date)	1,790,810
Term loans originated in 2019	335,126
Term loans originated in 2018	281,578
Term loans originated in 2017	287,150
Term loans originated in 2016	191,092
Term loans originated in 2015 and prior	239,070
Revolving loans	468,496
Total	3,593,322	$ 2,094,254
Other Commercial | Pass
Credit Quality Indicators By Origination
Term loans originated in 2020 (year-to-date)	1,784,359
Term loans originated in 2019	330,303
Term loans originated in 2018	275,011
Term loans originated in 2017	281,371
Term loans originated in 2016	188,849
Term loans originated in 2015 and prior	229,806
Revolving loans	453,105
Total	3,542,804
Other Commercial | Special Mention
Credit Quality Indicators By Origination
Term loans originated in 2020 (year-to-date)	606
Term loans originated in 2019	0
Term loans originated in 2018	0
Term loans originated in 2017	0
Term loans originated in 2016	0
Term loans originated in 2015 and prior	0
Revolving loans	0
Total	606
Other Commercial | Substandard
Credit Quality Indicators By Origination
Term loans originated in 2020 (year-to-date)	5,845
Term loans originated in 2019	4,820
Term loans originated in 2018	6,566
Term loans originated in 2017	5,323
Term loans originated in 2016	2,066
Term loans originated in 2015 and prior	8,100
Revolving loans	14,416
Total	47,136
Other Commercial | Doubtful/ Loss
Credit Quality Indicators By Origination
Term loans originated in 2020 (year-to-date)	0
Term loans originated in 2019	3
Term loans originated in 2018	1
Term loans originated in 2017	456
Term loans originated in 2016	177
Term loans originated in 2015 and prior	1,164
Revolving loans	975
Total	$ 2,776