CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Operating activities:
Net income	$ 32,408	$ 40,250
Noncash items:
Amortization of investment premiums	55,939	64,046
Amortization of equity-based awards	842	1,274
Other depreciation and amortization	53	59
Change in recorded measureable hedge ineffectiveness on interest rate swap agreements designated as cash flow hedges		899
Net change in receivables, other assets, accounts payable and accrued expenses	(6,082)	1,716
Net cash provided by operating activities	83,160	108,244
Investing activities:
Purchases of residential mortgage investments	(1,415,579)	(2,275,907)
Interest receivable acquired with the purchase of residential mortgage investments	(2,704)	(3,613)
Principal collections on residential mortgage investments, including changes in mortgage securities principal remittance receivable	1,721,856	1,913,662
Net cash provided by (used in) investing activities	303,573	(365,858)
Financing activities:
Proceeds from repurchase arrangements and similar borrowings	96,246,580	75,996,185
Principal payments on repurchase arrangements and similar borrowings	(96,640,768)	(75,687,347)
Increase (decrease) in cash collateral receivable from interest rate swap counterparties	8,876	(17,858)
Net proceeds from interest rate swap settlements	24,222	9,775
Proceeds from issuance of preferred shares		9,845
Common stock repurchases	(29,472)
Other capital stock transactions	(72)	(261)
Dividends paid	(42,603)	(50,231)
Net cash (used in) provided by financing activities	(433,237)	260,108
Net change in cash and cash equivalents	(46,504)	2,494
Cash and cash equivalents at beginning of period	103,907	56,732
Cash and cash equivalents at end of period	$ 57,403	$ 59,226