DEBT (Tables)

12 Months Ended

Dec. 31, 2018

DEBT [Abstract]

Debt

	Effective
in thousands	Interest Rates	2018	2017
Short-term Debt
Bank line of credit expires 20211, 2	1.25%	$        133,000	$                   0
Total short-term debt		$        133,000	$                   0
Long-term Debt
Bank line of credit expires 20211		$                   0	$        250,000
Term loan due 20183		0	350,000
Floating-rate notes due 2020	3.50%	250,000	250,000
Floating-rate notes due 2021	3.71%	500,000	0
7.50% notes due 2021		0	35,111
8.85% notes due 2021	8.88%	6,000	6,000
Term loan due 2021		0	250,000
4.50% notes due 2025	4.65%	400,000	400,000
3.90% notes due 2027	4.00%	400,000	400,000
7.15% notes due 2037	8.05%	129,239	240,188
4.50% notes due 2047	4.59%	700,000	700,000
4.70% notes due 2048	5.42%	460,949	0
Other notes	6.46%	208	230
Total long-term debt - face value		$     2,846,396	$     2,881,529
Unamortized discounts and debt issuance costs		(67,016)	(26,664)
Total long-term debt - book value		$     2,779,380	$     2,854,865
Less current maturities		23	41,383
Total long-term debt - reported value		$     2,779,357	$     2,813,482
Estimated fair value of long-term debt		$     2,695,802	$     2,983,419

1	Borrowings on the bank line of credit are classified as short-term debt if we intend to repay within twelve months and as long-term debt if we have the intent and ability to extend payment beyond twelve months.
2	The effective interest rate reflects the margin above LIBOR for LIBOR-based borrowings. We also paid upfront fees that are amortized to interest expense and pay fees for unused borrowing capacity and standby letters of credit.
3	This short-term loan was refinanced on a long-term basis in February 2018 as discussed below. Thus, it was classified as long-term debt as of December 31, 2017.

Schedule of Principal and Interest Debt Payments

in thousands	Total	Principal	Interest
Scheduled Debt Payments (excluding the line of credit)
2019	$      121,629	$             23	$    121,606
2020	366,366	250,025	116,341
2021	606,312	506,026	100,286
2022	96,041	28	96,013
2023	96,041	30	96,011

Standby Letters of Credit

in thousands
Standby Letters of Credit
Risk management insurance	$       38,111
Reclamation/restoration requirements	6,868
Total	$       44,979