Debt (Tables)

12 Months Ended

Dec. 31, 2017

Debt Disclosure [Abstract]

Schedule of Senior Notes

Our notes payable are summarized as follows ($000’s omitted):

	December 31,
	2017			2016
7.625% unsecured senior notes due October 2017	$	—		$	123,000
4.250% unsecured senior notes due March 2021 (a)	700,000			700,000
5.500% unsecured senior notes due March 2026 (a)	700,000			700,000
5.000% unsecured senior notes due January 2027 (a)	600,000			600,000
7.875% unsecured senior notes due June 2032 (a)	300,000			300,000
6.375% unsecured senior notes due May 2033 (a)	400,000			400,000
6.000% unsecured senior notes due February 2035 (a)	300,000			300,000
Net premiums, discounts, and issuance costs (b)	(13,057		)	(12,984		)
Total senior notes	$	2,986,943		$	3,110,016
Other notes payable	20,024			19,282
Notes payable	$	3,006,967		$	3,129,298
Estimated fair value	$	3,263,774		$	3,131,579

(a) Redeemable prior to maturity; guaranteed on a senior basis by certain wholly-owned subsidiaries.

(b) The carrying value of senior notes reflects the impact of premiums, discounts, and issuance costs that are amortized to interest cost over the respective terms of the senior notes

Schedule of Financial Services available credit lines

The following is aggregate borrowing information for our mortgage operations ($000’s omitted):

	December 31,
	2017			2016
Available credit lines	$	475,000		$	360,000
Unused credit lines	$	37,196		$	28,379
Weighted-average interest rate	3.55		%	2.89		%