CONSOLIDATED STATEMENTS OF CASH FLOWS $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Cash Flows from Operating Activities:
Net income	$ 67,560	$ 78,013	$ 136,191
Adjustments to reconcile net income to net cash provided by operating activities:
Net amortization (accretion)	7,648	542	(2,671)
Realized loss (gain) on investment securities and related hedges, net	3,645	4,617	(42,091)
Realized gain on distressed residential mortgage loans	(14,865)	(31,251)	(14,380)
Unrealized (gain) loss on investment securities and related hedges, net	(7,070)	2,641	7,667
Gain on de-consolidation of multi-family loans held in securitization trusts and multi-family collateralized debt obligations	0	(1,483)	0
Gain on remeasurement of existing membership interest in businesses acquired	(5,052)	0	0
Gain on bargain purchase on businesses acquired	(65)	0	0
Unrealized gain on loans and debt held in multi-family securitization trusts	(3,032)	(12,368)	(56,931)
Loss on extinguishment of debt	0	0	3,397
Net decrease in loans held for sale	432	323	87
(Recovery of) provision for loan losses	(838)	1,363	1,939
Income from unconsolidated entity, mezzanine loan and preferred equity investments	(22,202)	(12,997)	(4,562)
Distributions of income from unconsolidated entity, mezzanine loan and preferred equity investments	15,801	9,827	2,238
Amortization of stock based compensation, net	514	983	1,180
Changes in operating assets and liabilities:
Receivables and other assets	6,756	10,945	(3,631)
Accrued expenses and other liabilities and accrued expenses, related parties	4,612	(14,819)	9,118
Net cash provided by operating activities	53,844	36,336	37,551
Cash Flows from Investing Activities:
Acquisition of businesses, net of cash acquired	(28,468)	0	0
Restricted cash	(35,172)	33,448	(10,150)
Proceeds from sales of investment securities	208,229	99,235	93,578
Purchases of investment securities	(423,175)	(152,883)	(20,273)
Redemption (purchases) of FHLBI stock	5,445	(5,445)	0
Purchases of other assets	(103)	(61)	(254)
Funding of mezzanine loans, equity and preferred equity investments	(46,896)	(58,215)	(49,816)
Principal repayments received on mezzanine loans and preferred equity investments	4,464	4,308	5,590
Return of capital from investments in limited partnerships and limited liability companies	10,940	0	0
Net (payments) proceeds from other derivative instruments settled during the period	(933)	(5,766)	1,124
Principal paydowns on investment securities - available for sale	136,836	105,774	98,877
Proceeds from sale of real estate owned	2,131	1,044	3,882
Proceeds from sales of loans held in multi-family securitization trusts	0	65,587	0
Net cash provided by (used in) investing activities	33,662	283,965	(125,016)
Cash Flows from Financing Activities:
Proceeds from (payments made on) financing arrangements, net of FHLBI advances and payments	175,993	(99,011)	99,789
Payments made on securitized debt	166,347	0	0
Common stock issuance, net	13,496	31,799	296,546
Preferred stock issuance, net	0	86,862	0
Payments made on collateralized debt obligations	(126,018)	(116,136)	(75,796)
Early Repayment of Senior Debt	(16,255)	0	0
Net cash (used in) provided by financing activities	(65,911)	(333,940)	131,265
Net Increase (Decrease) in Cash and Cash Equivalents	21,595	(13,639)	43,800
Cash and Cash Equivalents - Beginning of Period	61,959	75,598	31,798
Cash and Cash Equivalents - End of Period	83,554	61,959	75,598
Supplemental Disclosure:
Cash paid for interest	300,992	307,162	352,232
Cash paid for income taxes	4,061	4,922	8,295
Non-Cash Investment Activities:
Purchase of investment securities not yet settled	148,015	227,969	283,537
Consolidation of multi-family loans held in securitization trusts	0	1,075,529	0
Consolidation of multi-family collateralized debt obligations	0	1,009,942	0
Common Stock
Cash Flows from Financing Activities:
Dividends paid	(105,108)	(113,318)	(86,705)
Non-Cash Financing Activities:
Dividends declared on stock to be paid in subsequent period	26,754	26,256	28,376
Preferred Stock
Cash Flows from Financing Activities:
Dividends paid	(12,900)	(9,218)	(5,812)
Non-Cash Financing Activities:
Dividends declared on stock to be paid in subsequent period	3,225	3,225	1,453
Financing arrangements, residential mortgage loans
Cash Flows from Investing Activities:
Principal repayments received on loans	23,648	28,166	12,687
Purchases of residential mortgage loans and distressed residential mortgage loans	(82,167)	(156,005)	(405,427)
Distressed residential mortgage loans held in securitization trusts (net)
Cash Flows from Investing Activities:
Principal repayments received on loans	122,552	238,798	64,715
Multi-family collateralized debt obligations
Cash Flows from Investing Activities:
Principal repayments received on loans	136,331	85,980	80,451
Residential collateralized debt obligations
Cash Flows from Financing Activities:
Payments made on collateralized debt obligations	(25,152)	(28,952)	(12,918)
Collateralized Loan Obligation
Cash Flows from Financing Activities:
Payments made on collateralized debt obligations	$ (136,314)	$ (85,966)	$ (83,839)