CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities:
Net earnings		$ 292,485,000	$ 265,371,000	$ 239,506,000
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation and amortization		174,398,000	173,720,000	149,101,000
Impairment losses – real estate and other charges, net of recoveries		28,211,000	4,953,000	11,294,000
Impairment – commercial mortgage residual interests valuation		0	0	6,830,000
Loss on early extinguishment of debt		18,240,000	0	0
Amortization of notes payable discount		3,263,000	1,788,000	1,394,000
Amortization of debt costs		4,611,000	3,502,000	3,086,000
Amortization of mortgages payable premium		(85,000)	(85,000)	(147,000)
Amortization of interest rate hedges		3,664,000	1,932,000	2,802,000
Settlement of forward starting swaps		4,080,000	(7,688,000)	13,345,000
Gain on disposition of real estate		(65,070,000)	(36,655,000)	(27,182,000)
Performance incentive plan expense		10,417,000	14,223,000	11,401,000
Performance incentive plan payment		(432,000)	(862,000)	(581,000)
Change in operating assets and liabilities, net of assets acquired and liabilities assumed:
Decrease in real estate leased to others using the direct financing method		874,000	884,000	1,364,000
Increase in receivables		(203,000)	(175,000)	(74,000)
Increase in accrued rental income		(747,000)	(1,752,000)	(252,000)
Decrease in other assets		793,000	1,960,000	1,663,000
Increase (decrease) in accrued interest payable		(792,000)	646,000	(448,000)
Increase (decrease) in other liabilities		(1,516,000)	(90,000)	2,636,000
Other		(282,000)	(115,000)	(401,000)
Net cash provided by operating activities		471,909,000	421,557,000	415,337,000
Cash flows from investing activities:
Proceeds from the disposition of real estate		148,476,000	97,245,000	104,117,000
Additions to real estate:
Accounted for using the operating method		(756,971,000)	(721,893,000)	(885,966,000)
Principal payments on mortgages and notes receivable		0	1,250,000	4,141,000
Other		(876,000)	(2,159,000)	(2,235,000)
Net cash used in investing activities		(609,371,000)	(625,557,000)	(779,943,000)
Cash flows from financing activities:
Proceeds from line of credit payable		1,599,500,000	1,501,700,000	1,330,200,000
Repayment of line of credit payable		(1,720,000,000)	(1,381,200,000)	(1,330,200,000)
Repayment of mortgages payable		(538,000)	(510,000)	(9,962,000)
Proceeds from notes payable		692,913,000	398,372,000	346,140,000
Repayment of notes payable		(300,000,000)	(250,000,000)	0
Payment for early extinguishment of debt		(18,240,000)	0	0
Payment of debt issuance costs		(7,156,000)	(7,837,000)	(3,362,000)
Proceeds from issuance of common stock		345,324,000	256,764,000	278,040,000
Stock issuance costs		(3,947,000)	(3,836,000)	(15,204,000)
Payment of common stock dividends		(303,164,000)	(277,120,000)	(257,007,000)
Noncontrolling interest distributions		0	(84,000)	(136,000)
Net cash provided by (used in) financing activities		250,365,000	(89,176,000)	644,886,000
Net increase (decrease) in cash, cash equivalents and restricted cash		112,903,000	(293,176,000)	280,280,000
Cash, cash equivalents and restricted cash at beginning of year	[1]	1,364,000	294,540,000	14,260,000
Cash, cash equivalents and restricted cash at end of year	[1]	114,267,000	1,364,000	294,540,000
Supplemental disclosure of cash flow information:
Interest paid, net of amount capitalized		107,861,000	103,761,000	91,403,000
Taxes received		0	(15,000)	(155,000)
Supplemental disclosure of noncash investing and financing activities:
Increase (decrease) in other comprehensive income		(8,042,000)	5,547,000	(12,161,000)
Change in lease classification (direct financing lease to operating lease)		565,000	696,000	1,924,000
Change in lease classification (operating lease to direct financing lease)		258,000	0	0
Series D Preferred Stock
Cash flows from financing activities:
Redemption of Series D preferred stock		0	(287,500,000)	0
Payment of preferred stock dividends		0	(3,598,000)	(19,047,000)
Series E Preferred Stock
Cash flows from financing activities:
Payment of preferred stock dividends		(16,387,000)	(16,387,000)	(16,387,000)
Series F Preferred Stock
Cash flows from financing activities:
Proceeds from issuance of Series F preferred stock		0	0	345,000,000
Payment of preferred stock dividends		$ (17,940,000)	$ (17,940,000)	$ (3,189,000)

[1] Cash, cash equivalents and restricted cash is the aggregate of cash and cash equivalents and restricted cash and cash held in escrow from the Consolidated Balance Sheets. NNN did not have restricted cash or cash held in escrow at December 31, 2018, 2017 and 2016.