CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 42,828	$ 35,152
Accounts receivable, net of allowance for doubtful accounts of $2,323 and $3,191 at December 31, 2017 and 2016, respectively	580,354	148,091
Federal and state income taxes receivable	1,152	2,126
Inventory	69,167	20,191
Other	53,354	41,322
Total current assets	746,855	246,882
Property and equipment, net	4,254,730	3,408,963
Goodwill and intangible assets	687,072	88,966
Deposits on equipment purchases	16,351	16,050
Deferred tax assets, net	3,875	4,124
Other	49,973	7,306
Total assets	5,758,856	3,772,291
Current liabilities:
Accounts payable	319,621	125,667
Accrued expenses	226,629	139,148
Total current liabilities	546,250	264,815
Borrowings under revolving credit facility	268,000
Long-term debt, net of debt issuance cost of $1,217 and $1,563 at December 31, 2017 and 2016, respectively	598,783	598,437
Deferred tax liabilities, net	350,836	650,661
Other	12,494	9,654
Total liabilities	1,776,363	1,523,567
Commitments and contingencies (see Note 8)
Stockholders’ equity:
Preferred stock, par value $.01; authorized 1,000,000 shares, no shares issued
Common stock, par value $.01; authorized 300,000,000 shares with 266,259,083 and 191,525,872 issued and 222,456,472 and 148,133,255 outstanding at December 31, 2017 and 2016, respectively	2,662	1,915
Additional paid-in capital	2,785,823	1,042,696
Retained earnings	2,105,897	2,116,341
Accumulated other comprehensive income (loss)	6,822	(1,134)
Treasury stock, at cost, 43,802,611 shares and 43,392,617 shares at December 31, 2017 and 2016, respectively	(918,711)	(911,094)
Total stockholders’ equity	3,982,493	2,248,724
Total liabilities and stockholders’ equity	$ 5,758,856	$ 3,772,291

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.