Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Cash flows from operating activities:
Net income (loss)	$ 91,552	$ 194,829
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
(Gain) loss on extinguishment/defeasance of debt	1,070	4,392
Depreciation and amortization	29,192	31,896
Unrealized (gain) loss on derivative instruments	(889)	(1,356)
Unrealized (gain) loss on equity securities	(1,341)	0
Unrealized (gain) loss on Agency interest-only securities	(38)	(456)
Unrealized (gain) loss on investment in mutual fund	(308)	(204)
Provision for loan losses	600	13,600
Impairment of real estate	1,350	0
Amortization of equity based compensation	18,336	6,667
Amortization of deferred financing costs included in interest expense	8,460	8,020
Amortization of premium on mortgage loan financing	(1,300)	(762)
Amortization of above- and below-market lease intangibles	(867)	(1,286)
Amortization of premium/(accretion) of discount and other fees on loans	(14,405)	(13,795)
Amortization of premium/(accretion) of discount and other fees on securities	82	2,944
Realized (gain) loss on sale of mortgage loan receivables held for sale	(38,589)	(12,893)
Realized (gain) loss on securities	(10,726)	4,896
Realized (gain) loss on sale of real estate, net	(963)	(96,341)
Realized gain on sale of derivative instruments	84	192
Origination of mortgage loan receivables held for sale	(554,115)	(1,115,218)
Purchases of mortgage loan receivables held for sale	(9,934)	0
Repayment of mortgage loan receivables held for sale	492	1,324
Proceeds from sales of mortgage loan receivables held for sale	574,303	926,889
(Income) loss from investments in unconsolidated joint ventures in excess of distributions received	(3,617)	(466)
Distributions from operations of investment in unconsolidated joint ventures	3,067	0
Deferred tax asset (liability)	7,405	(4,484)
Changes in operating assets and liabilities:
Accrued interest receivable	4,275	(1,968)
Other assets	(5,921)	7,503
Accrued expenses and other liabilities	(33,010)	(5,262)
Net cash provided by (used in) operating activities	64,245	(51,339)
Cash flows from investing activities:
Origination of mortgage loan receivables held for investment	(985,825)	(1,240,894)
Repayment of mortgage loan receivables held for investment	1,191,908	755,404
Purchases of real estate securities	(1,192,852)	(303,021)
Repayment of real estate securities	178,468	93,185
Basis recovery of Agency interest-only securities	9,339	14,898
Proceeds from sales of real estate securities	534,249	306,109
Purchases of real estate	(13,905)	(113,903)
Capital improvements of real estate	(3,606)	(4,822)
Proceeds from sale of real estate	10,794	153,398
Capital contributions and advances to investment in unconsolidated joint ventures	(56,393)	(370)
Capital distribution from investment in unconsolidated joint ventures	46,019	1,250
Capitalization of interest on investment in unconsolidated joint ventures	(142)	(1,074)
Purchase of FHLB stock	(3,704)	0
Proceeds from sale of FHLB stock	0	20,000
Purchase of derivative instruments	(210)	(305)
Sale of derivative instruments	101	114
Net cash provided by (used in) investing activities	(285,759)	(320,031)
Cash flows from financing activities:
Deferred financing costs paid	(4,453)	(2,975)
Proceeds from borrowings under debt obligations	10,186,669	4,401,648
Repayment of borrowings under debt obligations	(9,771,014)	(3,969,654)
Cash dividends paid to Class A common shareholders	(144,306)	(122,770)
Payment of liability assumed in exchange for shares for the minimum withholding taxes on vesting restricted stock	(8,106)	(837)
Purchase of treasury stock	(637)	0
Net cash provided by (used in) financing activities	244,817	273,600
Net increase (decrease) in cash, cash equivalents and restricted cash	23,303	(97,770)
Cash, cash equivalents and restricted cash at beginning of period	98,450	182,683
Cash, cash equivalents and restricted cash at end of period	121,753	84,913
Supplemental information:
Cash paid for interest, net of amounts capitalized	164,429	151,868
Cash paid (received) for income taxes	4,817	5,718
Non-cash investing and financing activities:
Securities and derivatives purchased, not settled	7,000	14
Securities and derivatives sold, not settled	3,962	0
Repayment in transit of mortgage loans receivable held for investment (other assets)	6,120	31,764
Repayment of mortgage loans receivable held for sale	128	0
Settlement of mortgage loan receivable held for investment by real estate, net	(17,851)	0
Transfer from mortgage loans receivable held for sale to mortgage loans receivable held for investment, net, at amortized cost	35,940	55,403
Proceeds from sale of real estate	0	1,421
Real estate acquired in settlement of mortgage loan receivable held for investment, net	17,851	0
Net settlement of sale of real estate, subject to debt - real estate	(11,943)	0
Net settlement of sale of real estate, subject to debt - debt obligations	11,943	0
Reduction in proceeds from sales of real estate	0	62,417
Assumption of debt obligations by real estate buyer/defeasance of debt and related costs	0	(62,417)
Exchange of noncontrolling interest for common stock	16,110	62,433
Change in deferred tax asset related to exchanges of noncontrolling interest for common stock	0	428
Increase in amount payable pursuant to tax receivable agreement	(11)	(86)
Rebalancing of ownership percentage between Company and Operating Partnership	147	869
Dividends declared, not paid	2,384	1,964
Stock dividends	23,824	0
Total cash, cash equivalents and restricted cash shown in the consolidated statement of cash flows	98,450	182,683
Consolidated Joint Venture
Cash flows from financing activities:
Capital distributed to noncontrolling interests	(1,013)	(24,400)
Capital contributed by noncontrolling interests in consolidated joint ventures	498	5,779
Operating Partnership
Cash flows from financing activities:
Capital distributed to noncontrolling interests	$ (12,821)	$ (13,191)