Lines of Credit and Financing Arrangements:

The following tables summarize our outstanding debt obligations and the classification in the accompanying Consolidated Balance Sheets (in millions):



	As of December 31,
	2017			2016
Short-Term Debt:
Asset Securitization Program	$	—		$	50.0
Foreign obligations	0.9			2.4
Total short-term debt	$	0.9		$	52.4
Current maturities of long-term debt:
Capital lease obligations	$	3.2		$	0.8
Domestic credit facility	30.0			—
Senior unsecured notes	—			200.0
Debt issuance costs	(0.6		)	(0.7		)
Total current maturities of long-term debt	$	32.6		$	200.1
Long-Term Debt:
Asset Securitization Program	$	276.0		$	—
Capital lease obligations	11.9			15.0
Domestic credit facility	337.0			256.0
Senior unsecured notes	350.0			350.0
Debt issuance costs	(4.4		)	(5.3		)
Total long-term debt	$	970.5		$	615.7
Total debt	$	1,004.0		$	868.2

As of December 31, 2017, the aggregate amounts of required principal payments on total debt were as follows (in millions):



2018	$	34.1
2019	306.3
2020	30.0
2021	277.0
2022	—
Thereafter	361.6

Short-Term Debt

Foreign Obligations

Through several of our foreign subsidiaries, we have available to us facilities to assist in financing seasonal borrowing needs for our foreign locations. We had $0.9 million and $2.4 million of foreign obligations as of December 31, 2017 and 2016, respectively, that were primarily borrowings under non-committed facilities. Proceeds on these facilities were $30.4 million, $28.4 million and $79.0 million during the years ended December 31, 2017, 2016 and 2015, respectively. Repayments on the facilities were $31.9 million, $30.8 million and $85.4 million during the years ended December 31, 2017, 2016 and 2015, respectively.

Asset Securitization Program

Under the Asset Securitization Program (“ASP”), we are eligible to sell beneficial interests in a portion of our trade accounts receivable to participating financial institutions for cash. The ASP contains a provision whereby we retain the right to repurchase all of the outstanding beneficial interests transferred. Our continued involvement with the transferred assets includes servicing, collection and administration of the transferred beneficial interests. The accounts receivable securitized under the ASP are high-quality domestic customer accounts that have not aged significantly. The receivables represented by the retained interest that we service are exposed to the risk of loss for any uncollectible amounts in the pool of receivables sold under the ASP. The fair values assigned to the retained and transferred interests are based on the sold accounts receivable carrying value given the short term to maturity and low credit risk. The sale of the beneficial interests in our trade accounts receivable are reflected as secured borrowings in the accompanying Consolidated Balance Sheets and proceeds received are included in cash flows from financing activities in the accompanying Consolidated Statements of Cash Flows.

Prior to the amendment on November 13, 2017, the ASP provided for a maximum securitization amount ranging from $200.0 million to $325.0 million, depending on the period. The ASP was amended effective as of November 13, 2017 to increase the maximum securitization range from $225.0 million to $380.0 million, depending on the period. The maximum capacity under the ASP is the lesser of the maximum securitization amount or 100% of the net pool balance less allowances, as defined by the ASP. Eligibility for securitization is limited based on the amount and quality of the qualifying accounts receivable and is calculated monthly. The eligible amounts available and beneficial interests sold were as follows (in millions):



	As of December 31,
	2017			2016
Eligible amount available under the ASP on qualified accounts receivable	$	290.0		$	250.0
Beneficial interest sold	(276.0		)	(50.0		)
Remaining amount available	$	14.0		$	200.0

We pay certain discount fees to use the ASP and to have the facility available to us. These fees relate to both the used and unused portions of the securitization. The used fee is based on the beneficial interest sold and calculated on either the average LIBOR rate or floating commercial paper rate determined by the purchaser of the beneficial interest, plus a program fee of 0.70%. The average rates as of December 31, 2017 and 2016 were 2.60% and 1.66%, respectively. The unused fee is based on 101% of the maximum available amount less the beneficial interest sold and calculated at a 0.35% fixed rate throughout the term of the agreement. We recorded these fees in Interest expense, net in the accompanying Consolidated Statements of Operations.

The ASP contains certain restrictive covenants relating to the quality of our accounts receivable and cross-default provisions with our Sixth Amended and Restated Credit Facility Agreement ("Domestic Credit Facility"), senior unsecured notes and any other indebtedness we may have over $75.0 million. The administrative agent under the ASP is also a participant in our Domestic Credit Facility. The participating financial institutions have investment grade credit ratings. We continue to evaluate their credit ratings and have no reason to believe they will not perform under the ASP. As of December 31, 2017, we believe we were in compliance with all covenant requirements.

Long-Term Debt

Domestic Credit Facility

On August 30, 2016, we replaced an earlier credit facility with the Domestic Credit Facility, which consists of a $650.0 million unsecured revolving credit facility and a $250.0 million unsecured term loan and matures in August 2021 (the "Maturity Date"). Under our Domestic Credit Facility, we had outstanding borrowings of $367.0 million, of which $220.0 million was the term loan balance, as well as $2.9 million committed to standby letters of credit as of December 31, 2017. Subject to covenant limitations, $500.1 million was available for future borrowings. The unsecured term loan also matures on the Maturity Date and requires quarterly principal repayments of $7.5 million beginning in March 2017; however, we made $30.0 million of required principal repayments for 2017 in November 2016. The revolving credit facility allows up to $100.0 million of letters of credit to be issued and also includes a subfacility for swingline loans of up to $65.0 million. Additionally, at our request and subject to certain conditions, the commitments under the Domestic Credit Facility may be increased by a maximum of $350.0 million as long as existing or new lenders agree to provide such additional commitments.

Our weighted average borrowing rate on the facility was as follows:



	As of December 31,
	2017		2016
Weighted average borrowing rate	2.76	%	2.00	%

Our Domestic Credit Facility is guaranteed by certain of our subsidiaries and contains financial covenants relating to leverage and interest coverage. Other covenants contained in the Domestic Credit Facility restrict, among other things, certain mergers, asset dispositions, guarantees, debt, liens, and affiliate transactions. The financial covenants require us to maintain a defined Consolidated Indebtedness to Adjusted EBITDA Ratio and a Cash Flow (defined as EBITDA minus capital expenditures) to Net Interest Expense Ratio. The required ratios under our Domestic Credit Facility are detailed below:



Consolidated Indebtedness to Adjusted EBITDA Ratio no greater than	3.5 : 1.0
Cash Flow to Net Interest Expense Ratio no less than	3.0 : 1.0

Our Domestic Credit Facility contains customary events of default. These events of default include nonpayment of principal or other amounts, material inaccuracy of representations and warranties, breach of covenants or other restrictions or requirements, default on certain other indebtedness or receivables securitizations (cross default), certain voluntary and involuntary bankruptcy events and the occurrence of a change in control. A cross default under our Domestic Credit Facility could occur if:


•	We fail to pay any principal or interest when due on any other indebtedness or receivables securitization of at least $75.0 million; or


•	We are in default in the performance of, or compliance with any term of any other indebtedness or receivables securitization in an aggregate principal amount of at least $75.0 million or any other condition exists which would give the holders the right to declare such indebtedness due and payable prior to its stated maturity.

Each of our major debt agreements contains provisions by which a default under one agreement causes a default in the others (a cross default). If a cross default under the Domestic Credit Facility, our senior unsecured notes, our lease of our corporate headquarters in Richardson, Texas (recorded as an operating lease), or our ASP were to occur, it could have a wider impact on our liquidity than might otherwise occur from a default of a single debt instrument or lease commitment.

If any event of default occurs and is continuing, lenders with a majority of the aggregate commitments may require the administrative agent to terminate our right to borrow under our Domestic Credit Facility and accelerate amounts due under our Domestic Credit Facility (except for a bankruptcy event of default, in which case such amounts will automatically become due and payable and the lenders’ commitments will automatically terminate). As of December 31, 2017, we believe we were in compliance with all covenant requirements.

Senior Unsecured Notes

We issued $350.0 million of senior unsecured notes in November 2016 (the "Notes") which will mature on November 15, 2023 with interest being paid on May 15 and November 15 at 3.00% per annum semiannually. We also repaid $200.0 million of senior unsecured notes issued in 2010 which matured on May 15, 2017. The Notes are guaranteed, on a senior unsecured basis, by each of our domestic subsidiaries that guarantee indebtedness under our Domestic Credit Facility. The indenture governing the Notes contains covenants that, among other things, limit our ability and the ability of the subsidiary guarantors to: create or incur certain liens; enter into certain sale and leaseback transactions; and enter into certain mergers, consolidations and transfers of substantially all of our assets. The indenture also contains a cross default provision which is triggered if we default on other debt of at least $75 million in principal which is then accelerated, and such acceleration is not rescinded within 30 days of the notice date. As of December 31, 2017, we believe we were in compliance with all covenant requirements.