Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Statement of Cash Flows [Abstract]
Net cash provided by operating activities	$ 117,611	$ 78,825
Cash flows from investing activities:
Sale of investment securities	22,396	67,033
Maturities of investment securities	93,368	343
Purchase of investment securities	(109,891)	(56,691)
Proceeds from sale or liquidation of long-term investments	466	1,000
Purchase of long-term investments	(26,000)	(50)
Investments in real estate ventures	(8,454)	(11,806)
Distributions from investments in real estate ventures	23,338	17,983
Increase in cash surrender value of life insurance policies	(854)	(393)
(Increase) decrease in restricted assets	(1,235)	2,674
Issuance of notes receivable	(1,500)	0
Proceeds from sale of fixed assets	75	5
Capital expenditures	(8,346)	(7,615)
Pay downs of investment securities	1,620	4,926
Investments in real estate, net	(205)	(81)
Net cash (used in) provided by investing activities	(15,222)	17,328
Cash flows from financing activities:
Proceeds from issuance of debt	850,020	243,282
Deferred financing costs	(19,200)	(6,600)
Repayments of debt	(836,145)	(2,917)
Borrowings under revolver	110,979	89,695
Repayments on revolver	(129,479)	(80,223)
Dividends and distributions on common stock	(104,750)	(97,846)
Contributions from non-controlling interest	0	248
Distributions to non-controlling interest	(165)	(7,422)
Proceeds from issuance of Vector common stock	43,230	0
Net cash (used in) provided by financing activities	(85,510)	138,217
Net increase in cash and cash equivalents	16,879	234,370
Cash and cash equivalents, beginning of period	393,530	240,368
Cash and cash equivalents, end of period	$ 410,409	$ 474,738