Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Cash flows from operating activities:
Net income (loss)	$ 60,604	$ 111,365
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
(Gain) loss on extinguishment/defeasance of debt	1,070	69
Depreciation and amortization	20,162	21,479
Unrealized (gain) loss on derivative instruments	(1,511)	(2,340)
Unrealized (gain) loss on equity securities	(1,088)	0
Unrealized (gain) loss on Agency interest-only securities	(22)	(313)
Unrealized (gain) loss on investment in mutual fund	(254)	(124)
Provision for loan losses	600	3,300
Impairment of real estate	1,350	0
Amortization of equity based compensation	14,761	4,505
Amortization of deferred financing costs included in interest expense	5,721	4,984
Amortization of premium on mortgage loan financing	(774)	(499)
Amortization of above- and below-market lease intangibles	(397)	(940)
Amortization of premium/(accretion) of discount and other fees on loans	(10,294)	(8,942)
Amortization of premium/(accretion) of discount and other fees on securities	(87)	2,270
Realized (gain) loss on sale of mortgage loan receivables held for sale	(27,342)	(11,032)
Realized (gain) loss on securities	(7,329)	2,342
Realized (gain) loss on sale of real estate, net	1,119	(32,637)
Realized gain on sale of derivative instruments	108	192
Origination of mortgage loan receivables held for sale	(333,342)	(764,948)
Repayment of mortgage loan receivables held for sale	370	286
Proceeds from sales of mortgage loan receivables held for sale	430,649	843,214
(Income) loss from investments in unconsolidated joint ventures in excess of distributions received	(2,522)	(65)
Distributions from operations of investment in unconsolidated joint ventures	3,067	0
Deferred tax asset (liability)	6,336	1,483
Changes in operating assets and liabilities:
Accrued interest receivable	2,705	(1,757)
Other assets	(6,310)	(793)
Accrued expenses and other liabilities	(24,805)	2,507
Net cash provided by (used in) operating activities	132,545	173,606
Cash flows from investing activities:
Purchase of derivative instruments	(159)	(205)
Sale of derivative instruments	50	114
Purchases of real estate securities	(827,999)	(199,135)
Repayment of real estate securities	110,443	56,707
Proceeds from sales of real estate securities	384,356	161,518
Purchase of FHLB stock	(3,704)	0
Origination of mortgage loan receivables held for investment	(484,496)	(914,489)
Repayment of mortgage loan receivables held for investment	781,916	431,030
Basis recovery of Agency interest-only securities	6,413	10,453
Capital contributions and advances to investment in unconsolidated joint ventures	(56,424)	(370)
Capital distribution from investment in unconsolidated joint ventures	38,625	1,250
Capitalization of interest on investment in unconsolidated joint ventures	(142)	(676)
Purchases of real estate	(5,071)	(114,184)
Capital improvements of real estate	(1,707)	(3,290)
Proceeds from sale of real estate	8,521	90,806
Net cash provided by (used in) investing activities	(49,378)	(480,471)
Cash flows from financing activities:
Deferred financing costs paid	(4,453)	(2,664)
Proceeds from borrowings under debt obligations	6,377,515	2,919,776
Repayment of borrowings under debt obligations	(6,213,678)	(2,588,483)
Cash dividends paid to Class A common shareholders	(108,240)	(91,220)
Purchase of treasury stock	637	0
Payment of liability assumed in exchange for shares for the minimum withholding taxes on vesting restricted stock	(8,083)	(837)
Net cash provided by (used in) financing activities	33,816	218,921
Net increase (decrease) in cash, cash equivalents and restricted cash	116,983	(87,944)
Cash, cash equivalents and restricted cash at beginning of period	98,450	182,683
Cash, cash equivalents and restricted cash at end of period	215,433	94,739
Supplemental information:
Cash paid for interest, net of amounts capitalized	98,832	87,675
Cash paid (received) for income taxes	3,591	6,266
Non-cash investing and financing activities:
Securities and derivatives purchased, not settled	25,500	(44,786)
Securities and derivatives sold, not settled	5	0
Repayment in transit of mortgage loans receivable held for investment (other assets)	0	66,094
Repayment of mortgage loans receivable held for sale	127	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, at amortized cost	15,504	55,403
Proceeds from sale of real estate	0	638
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	7,144	0
Net settlement of sale of real estate, subject to debt - debt obligations	7,144	0
Reduction in proceeds from sales of real estate	0	11,050
Assumption of debt obligations by real estate buyer/defeasance of debt and related costs	0	(11,050)
Exchange of noncontrolling interest for common stock	16,109	59,654
Change in deferred tax asset related to exchanges of noncontrolling interest for common stock	0	(226)
Increase in amount payable pursuant to tax receivable agreement	(11)	(86)
Rebalancing of ownership percentage between Company and Operating Partnership	(298)	653
Dividends declared, not paid	1,860	1,582
Stock dividends	23,823	0
Total cash, cash equivalents and restricted cash shown in the consolidated statement of cash flows	215,433	182,683
Consolidated Joint Venture
Cash flows from financing activities:
Capital distributed to noncontrolling interests	(262)	(13,792)
Capital contributed by noncontrolling interests in consolidated joint ventures	191	5,040
Operating Partnership
Cash flows from financing activities:
Capital distributed to noncontrolling interests	$ (8,537)	$ (8,899)